The correct expression that is equal to 4.6 is option c. [1.6 + (3 × 4)] – (2 ÷ 2)
Let's evaluate each expressions using the BODMAS rule of mathematics,
a. 1.6 + (3 × 4) – 2 ÷ 2
= 1.6 + 12 - 1
= 12.6
b. 1.6 + 3 × 4 – 2 ÷ 2
= 1.6 + 12 - 1
= 12.6
c. [1.6 + (3 × 4)] – (2 ÷ 2)
= [1.6 + 12] - 1
= 12.6
d. (1.6 + 3) × (4 – 2) ÷ 2
= 4.6 × 2 ÷ 2
= 4.6
BODMAS is an acronym used to remember the order of operations in mathematics: Brackets, Orders, Division, Multiplication, Addition, Subtraction. It is used to perform calculations in the correct order to obtain the correct result. Therefore, the correct answer is (c).
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Complete question - Which expression is equal to 4.6?
a. 1.6 + (3 × 4) – 2 ÷ 2
b. 1.6 + 3 × 4 – 2 ÷ 2
c. [1.6 + (3 × 4)] – (2 ÷ 2)
d. (1.6 + 3) × (4 – 2) ÷ 2
verify that the equation is an identity. 2cosx2x/sin2x=cotx-tanx
The LHS is equal to the RHS, and the given equation is verified as an identity. We have to verify that the following equation is an identity:
2cos(x) 2x / sin2(x) = cot(x) - tan(x)
Starting from the left-hand side (LHS):
2cos(x) 2x / sin2(x) = 2cos(x) 2x / (1 - cos2(x)) (using the identity sin2(x) = 1 - cos2(x))
= 2cos(x) 2x / (1 - cos(x)) (1 + cos(x))
= 2cos(x) 2x / (1 - cos(x)) (1 + cos(x)) (multiplying the denominator by (1 + cos(x)))
= 2cos(x) 2x / (1 - cos2(x))
= 2cos(x) 2x / sin2(x) (using the identity 1 - cos2(x) = sin2(x))
= 2cos(x) / sin(x) (simplifying by canceling out the common factor of 2 and cos(x))
= 2cos(x) / sin(x) * (cos(x) / cos(x)) (multiplying by 1 in the form of cos(x)/cos(x))
= 2cos2(x) / (sin(x)cos(x))
= 2cos(x)/sin(x) * cos(x)
= cot(x) * cos(x)
Now, moving to the right-hand side (RHS):
cot(x) - tan(x) = cos(x)/sin(x) - sin(x)/cos(x)
= cos2(x)/sin(x)cos(x) - sin2(x)/sin(x)cos(x)
= (cos2(x) - sin2(x))/sin(x)cos(x)
= cos(x)/sin(x) * cos(x)/cos(x) - sin(x)/cos(x) * sin(x)/sin(x) (using the identity cos2(x) - sin2(x) = cos(x)cos(x) - sin(x)sin(x))
= cot(x) * cos(x)
Therefore, the LHS is equal to the RHS, and the given equation is verified as an identity.
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A man buys a plot of agricultural land for rs. 300000 he sells 1/3rd at a loss of 20% and 2/5ths at a gain of 25% at what price must he sell the remaining land so as to make an overall profit of 10%
4x - 2y = -1
8x - 4y = -2
what method is most efficient to use and what is the answer
Whats the volume of the rectangular prism 9in 3in 2in
Answer:
54
Step-by-step explanation:
9x 3 x2 =54
what fraction is less greater than 1/2 and less than 4/5
A fraction that is greater than 1/2 and less than 4/5, we need to consider fractions between these two values. A fraction that is greater than 1/2 and less than 4/5 is 6/10.
Compare the two given fractions by finding a common denominator.
The lowest common denominator for 1/2 and 4/5 is 10.
Convert both fractions to equivalent fractions with a denominator of 10.
1/2 = 5/10
4/5 = 8/10
Identify a fraction between 5/10 and 8/10.
One possible fraction between these two is 6/10.
A fraction that is greater than 1/2 and less than 4/5 is 6/10.
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Plss someone answer this math question
The value of the reflex angle in this figure is 273 degrees
What is a reflex angle?A reflex angle is an angle that is more than 180 degrees and less than 360 degrees. For example, 270 degrees is a reflex angle. In geometry, there are different types of angles such as acute, obtuse and right angles, which are under 180 degrees.
In this given figure, there's acute angle and an obtuse angle, therefore a reflex angle must be present.
To find the reflex angle in the figure, we have to trace the green part of the figure which will give us;
180° + 93°
i.e the sum of angle on a straight line with an obtuse angle
Reflex angle = 180 + 93 = 273°
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Find the Differentials of
1) z = x^2 - xy^2 + 4y^5
2) f(x,y) = (3x-y)/(x+2y)
3) f(x,y) = xe^x3y
1) To find the differentials of z = x^2 - xy^2 + 4y^5, we can use the total differential formula:
dz = (∂z/∂x)dx + (∂z/∂y)dy
Taking the partial derivatives of z with respect to x and y:
∂z/∂x = 2x - y^2
∂z/∂y = -2xy + 20y^4
Substituting these into the total differential formula:
dz = (2x - y^2)dx + (-2xy + 20y^4)dy
2) To find the differentials of f(x,y) = (3x-y)/(x+2y), we can again use the total differential formula:
df = (∂f/∂x)dx + (∂f/∂y)dy
Taking the partial derivatives of f with respect to x and y:
∂f/∂x = (y-3)/(x+2y)^2
∂f/∂y = (3x-2y)/(x+2y)^2
Substituting these into the total differential formula:
df = [(y-3)/(x+2y)^2]dx + [(3x-2y)/(x+2y)^2]dy
3) To find the differentials of f(x,y) = xe^x3y, we can once again use the total differential formula:
df = (∂f/∂x)dx + (∂f/∂y)dy
Taking the partial derivatives of f with respect to x and y:
∂f/∂x = e^(x3y) + 3xye^(x3y)
∂f/∂y = 3x^2e^(x3y)
Substituting these into the total differential formula:
df = (e^(x3y) + 3xye^(x3y))dx + (3x^2e^(x3y))dy
Here are the results:
1) For z = x^2 - xy^2 + 4y^5, the partial derivatives are:
∂z/∂x = 2x - y^2
∂z/∂y = -2xy + 20y^4
2) For f(x,y) = (3x-y)/(x+2y), the partial derivatives are:
∂f/∂x = (3(x+2y) - 3(3x-y))/(x+2y)^2
∂f/∂y = (-1(x+2y) + (x+2y))/(x+2y)^2
3) For f(x,y) = xe^(x^3y), the partial derivatives are:
∂f/∂x = e^(x^3y) * (1 + 3x^2y)
∂f/∂y = xe^(x^3y) * x^3
These partial derivatives represent the differentials for each respective function.
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A museum sells stone souvenirs shaped like a cone with a diameter of 4.2 centimeters and a height of 9.5 centimeters. What is the volume of each souvenir? Round to the nearest tenth
PLEASE HURRY
the volume of each souvenir is 43. 85 cm³
How to determine the volumeThe formula for calculating the volume of a cone is represented as;
V = 1/3 πr²h
Given that;
V is the volumer is the radius of the coneh is the height of the coneThen,
r = diameter/2 = 4.2 /2 = 2.1 centimeters
Substitute the values, we have
Volume = 1/3 × 3.14 × 2.1² × 9.5
find the square, we have;
Volume = 1/3 × 3.14 × 4. 41 × 9.5
Multiply the values
Volume = 131. 5503/3
divide the values
Volume = 43. 85 cm³
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A chef is going to use a mixture of two brands of Italian dressing. The first brand contains 5% vinegar, and the second brand contains 8% vinegar. The chef wants to make 300 milliliters of a dressing that is 7% vinegar. How much of each brand should she use?
First Brand: ?
Second Brand: ?
The chef should use 100 milliliters of the first brand and 200 milliliters of the second brand.
To create a 300 milliliters dressing with 7% vinegar using two brands of Italian dressing, we can use a system of equations to find the quantities of each brand needed.
Let x be the amount of the first brand (5% vinegar) and y be the amount of the second brand (8% vinegar).
First equation (total volume):
x + y = 300
Second equation (vinegar percentage):
0.05x + 0.08y = 0.07 * 300
Now, solve the system of equations:
From the first equation, y = 300 - x
Substitute this into the second equation:
0.05x + 0.08(300 - x) = 21
Expand and simplify:
0.05x + 24 - 0.08x = 21
0.03x = -3
Now, divide by 0.03:
x = 100
Now, find the value of y:
y = 300 - x = 300 - 100 = 200
So, the chef should use 100 milliliters of the first brand and 200 milliliters of the second brand.
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Can someone help me I'm stuck.
Alexandria rolled a number cube 60 times and recorded her results in the table.
What is the theoretical probability of rolling a one or two? Leave as a fraction in simplest from
The theoretical probability of rolling a one or two on a number cube is 2/5 or 0.4.
To find the theoretical probability of rolling a one or two on a number cube, we need to determine the number of outcomes that correspond to rolling a one or two, and divide that by the total number of possible outcomes.
From the table, we can see that Alexandria rolled a one or two a total of 24 times out of 60 rolls. This means that the probability of rolling a one or two is: P(1 or 2) = 24/60
Simplifying the fraction by dividing both the numerator and denominator by the greatest common factor, we get: P(1 or 2) = 4/10
This can be further reduced to: P(1 or 2) = 2/5
Therefore, the theoretical probability of rolling a one or two on a number cube is 2/5 or 0.4.
In summary, the theoretical probability is the expected probability of an event occurring, based on mathematical reasoning. Here, we used the number of favorable outcomes to calculate the probability of rolling a one or two, and expressed the answer as a fraction in simplest form.
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How many grams of magnesium sulfate would be produced from the following reaction if 176 kJ of energy is absorbed by the reaction.
Al2(SO4)3 + 3 MgI2 → 2 AlI3 + 3 Mg(SO4) ΔH = +722 kJ
The amount of magnesium sulfate produced from the given reaction cannot be determined solely from the energy absorbed by the reaction.
Can the amount of magnesium sulfate produced from the reaction?
The given reaction is: Al2(SO4)3 + 3 MgI2 → 2 AlI3 + 3 Mg(SO4) and the enthalpy change for the reaction is ΔH = +722 kJ. The enthalpy change indicates that the reaction is endothermic, meaning that energy is absorbed by the reaction. The question asks about the amount of magnesium sulfate produced, which is not directly related to the energy absorbed by the reaction.
The balanced chemical equation shows that the reaction produces 3 moles of magnesium sulfate for every 3 moles of magnesium iodide consumed. Therefore, the amount of magnesium sulfate produced depends on the amount of magnesium iodide consumed.
To determine the amount of magnesium sulfate produced, we would need information about the amount of magnesium iodide consumed. The energy absorbed by the reaction does not provide enough information to determine the amount of magnesium sulfate produced.
In summary, the amount of magnesium sulfate produced from the given reaction cannot be determined solely from the energy absorbed by the reaction.
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Find the Riemann sum S₅ for the following information. Round your answer to the nearest hundredth. f(x) = 64 - x²; [a, b] = (-8, -3]; n = 5.c₁ = -7.5.c² = -6.5.c₃ = -5.5.c₄ = - 4.5.c₅ = -3.5
The Rounding to nearest hundredth, we get S₅ ≈ -12.25
How to find the Riemann sum S₅?The formula for a Riemann sum with n subintervals is:
[tex]S_n[/tex]= ∑ᵢ₌₁ⁿ f(cᵢ) Δx,
where Δx = (b - a)/n is the width of each subinterval and cᵢ is a point in the i-th subinterval. The value of cᵢ can be chosen arbitrarily, but here we are given specific values for c₁, c₂, c₃, c₄, and c₅.
In this problem, we have:
f(x) = 64 - x²
[a, b] = (-8, -3]
n = 5
Δx = (b - a)/n = (-3 - (-8))/5 = 1
Therefore, the width of each subinterval is 1.
The Riemann sum S₅ is:
S₅ = f(c₁) Δx + f(c₂) Δx + f(c₃) Δx + f(c₄) Δx + f(c₅) Δx
Substituting the given values for c₁, c₂, c₃, c₄, and c₅, we get:
S₅ = f(-7.5) + f(-6.5) + f(-5.5) + f(-4.5) + f(-3.5)
where f(x) = 64 - x².
Evaluating each term, we get:
f(-7.5) = 64 - (-7.5)² = 17.75
f(-6.5) = 64 - (-6.5)² = 5.75
f(-5.5) = 64 - (-5.5)² = -2.75
f(-4.5) = 64 - (-4.5)² = -12.25
f(-3.5) = 64 - (-3.5)² = -20.75
Therefore,
S₅ = 17.75(1) + 5.75(1) - 2.75(1) - 12.25(1) - 20.75(1) = -12.25.
Rounding to the nearest hundredth, we get S₅ ≈ -12.25.
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Find the area of the surface extending upward from the circle x^2 + y^2 = 1 in the cy-plane to the plane z = 2 - x - y.
The area of the surface is π square units.
We can use a surface integral to find the area of the surface. The surface integral of a scalar function f over a surface S is given by:
∬S f dS
In this case, we want to find the area of the surface, so f = 1, and the integral reduces to:
∬S dS
We can parameterize the surface S using cylindrical coordinates:
x = r cosθ
y = r sinθ
z = 2 - r cosθ - r sinθ
The surface S is defined by the equation x^2 + y^2 = 1, which in cylindrical coordinates is r^2 = 1. Therefore, the surface integral becomes:
∬S dS = ∫∫R ||rθ|| dr dθ
where R is the region in the rθ-plane that corresponds to the surface S.
To find the limits of integration for r and θ, we need to determine the bounds of the region R. Since r^2 = 1, we have r = 1 for all θ. The region R is therefore a circle of radius 1 centered at the origin, and we can integrate over the full range of θ:
∫0^2π ∫0^1 r dr dθ = π
Therefore, the area of the surface is π square units.
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Please help im begging you!!!
the perimeter of the trapezoid is 8x + 18. find the missing length of the lower base
Length of bottom base = 8x + 18 - (unknown)
To get the missing length of the lower base of the trapezoid, we need to use the formula for the perimeter of a trapezoid:
Perimeter = sum of all sides
For a trapezoid, this means:
Perimeter = length of top base + length of bottom base + length of left side + length of right side
In this case, we know that the perimeter is 8x + 18. We also know that the length of the top base and the lengths of the left and right sides are not given, so we'll just represent them with variables:
Perimeter = (length of top base) + (length of bottom base) + (length of left side) + (length of right side)
8x + 18 = (unknown) + (length of bottom base) + (unknown) + (unknown)
Simplifying: 8x + 18 = length of bottom base + (unknown)
Now we just need to isolate the length of the bottom base:
8x + 18 - (unknown) = length of bottom base
We can't simplify this any further without more information about the trapezoid, but we can say that the missing length of the lower base is:
Length of bottom base = 8x + 18 - (unknown)
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for each of the following situations identify the relation as linear quadratic or exponential. a. Larry is paid $10 per hour he receives a $1 per hour raise each year
The problem represents a linear equation.
What is linear equation?
A linear equation is a particular type of equation in which the highest power of the variable is always 1(linear). This type of equation is also known as a one-degree equation.
Larry is paid $10 per hour he receives a $1 per hour raise each year.
Let he works for x hours.
In 1 hour he receives $10 so for x hours he will receive $10x
$1 per hour raise.
So there will be a linear equation
The linear equation will be if we take total income as $y then,
y= 10x+1
which is of the linear equation form y=m x+ b where m is the slope.
Hence, the problem represents a linear equation.
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Last question find measure of arc Su
Check the picture below.
[tex]52x=\cfrac{154-50x}{2}\implies 104x=154-50x\implies 154x=154\implies x=\cfrac{154}{154} \\\\\\ x=1\hspace{9em}\stackrel{ 50(1) }{\widehat{SU}=50^o}[/tex]
6
The expression √532 + 46√3 is equivalent to the expression r + p, where r and p are positive
integers. What is the value of r + p?
The value of r+p in the expression is 2(√133 + 23√3)
To simplify the given expression, we need to first simplify the square root of 532.
We can factor 532 as 2 × 2 × 7 × 19, and then group the factors in pairs of two to simplify the square root:
√532 = √(2 × 2 × 7 × 19) = √(2 × 2) × √(7 × 19)
= 2√(7 × 19)
= 2√133
Now we can substitute this expression into the original expression and combine like terms:
√532 + 46√3
= 2√133 + 46√3
= 2√133 + 2(23√3)
= 2(√133 + 23√3)
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A circle is placed in a square with a side length of 8 m, as shown below. Find the area of the shaded region.
Use the value 3.14 for pi, and do not round your answer. Be sure to include the correct unit in your answer.
The area of the shaded region is the expression 16(4 - π) square metres.
How to evaluate for the shaded regionThe shaded region is the remaining area in the square which is outside the circle, so it is derived by subtracting the area of the circle from the area of the square as follows:
area of the square = 8 m × 8 m
area of the square = 64 m²
area of the circle = π × 4 m × 4 m
area of the circle = 16π m²
area of the shaded region = 64 m² - 16π m²
area of the shaded region = 16(4 - π) m²
Therefore, the area of the shaded region is the expression 16(4 - π) square metres.
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Determine the measure of arc cad thanks grade 9-10-11 it is either 240 or 260
The measure of arc CAD is either 240 or 260.
How to do measure of arc?Without additional information, it is not possible to determine the measure of arc CAD with certainty. The measure of an arc depends on the central angle that subtends it.
If the central angle is known, the measure of the arc can be calculated using the formula: measure of arc = (central angle / 360) x circumference of the circle. However, without knowing the central angle, we cannot determine the measure of arc CAD.
Therefore, we need to be provided with additional information such as the measure of another angle that is related to the central angle, or the length of a chord that subtends the arc in order to determine the central angle and the measure of arc CAD.
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4/625 x 625/9 cross cancellation
Answer:
Step-by-step explanation:
4/625 x 625/9 = 4 x 1 / 5 x 5 x 5 x 1 = 4/625. The cross cancellation did not change the result.
A large box of chocolates has a width that is 2 times the height of the box and a length that is 1. 5 times the width of
the box. Each of the 48 chocolates rests in a cube with a side length of 1 inch
Let's start by using algebra to represent the relationships between the dimensions of the box:
Let h be the height of the box. Then the width of the box is 2h (since it is 2 times the height). And the length of the box is 1.5 times the width, so it is 1.5(2h) = 3h.So the dimensions of the box are: height = h, width = 2h, length = 3h.
Now let's find the volume of the box:
Volume = height x width x length Volume = h x 2h x 3h Volume = [tex]6h^3[/tex]Since we know that each chocolate rests in a cube with a side length of 1 inch, the volume of each chocolate is [tex]1^3 = 1[/tex] cubic inch. So the total volume of all 48 chocolates is 48 cubic inches.
Therefore, we can set up an equation to solve for h:
[tex]48 = (6h^3) / (1 cubic inch/chocolate)[/tex]
[tex]48 = 6h^3[/tex]
[tex]8 = h^3[/tex]
h = 2
So the height of the box is 2 inches, the width is 4 inches (since it is 2 times the height), and the length is 6 inches (since it is 1.5 times the width).
To check our work, we can calculate the volume of the box:
Volume = height x width x length
Volume = 2 x 4 x 6
Volume = 48 cubic inches
This matches the total volume of all 48 chocolates, so we can be confident in our answer.
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The drawing shows a bridge design. the measurement of angle 1 is 125°. the measurement of angle 1 and angle 2 equal 180°. classify the relationship between angle 1 and 2, then find the measurement of angle 2.
The measurement of angle 2 is 55°, if the measurement of angle 1 and angle 2 equal 180° and measurement of angle 1 is 125° in the drawing of the bridge design.
The measurement of angle 1 is 125°, and the sum of angle 1 and angle 2 is 180°. The relationship between angle 1 and angle 2 is supplementary since their sum is equal to 180°. To find the measurement of angle 2,
Recall the given information: angle 1 = 125°, and angle 1 + angle 2 = 180°.Set up an equation using the supplementary relationship: 125° + angle 2 = 180°.Subtract 125° from both sides of the equation: angle 2 = 180° - 125°.Calculate the result: angle 2 = 55°.Therefore, angle 2 has a measurement of 55°.
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How do I find the value of X
Answer:
x = 30
Step-by-step explanation:
you can find it by vertical opposite angle which is their non adjecent angle are equal.
2x- 30 = 30
2x = 30 + 30 ..... take 30 to the left it change sighn
2x /2 = 60 / 2 ..... divided both side by 3
x = 30 ..... so the unknown no. is 30
What is the domain of the function y=^3/x-1?
The domain of the function y = (3/x) - 1 is all real numbers except x = 0
The domain of a function consists of all the valid input values for which the function is defined. In the case of the function y = (3/x) - 1, the only restriction on the domain arises from the presence of the variable x in the denominator.
To determine the domain, we need to find the values of x for which the expression 3/x is defined. Division by zero is undefined, so we must exclude any value of x that makes the denominator equal to zero.
In this case, we set the denominator, x, equal to zero and solve for x:
x = 0
Therefore, x cannot be equal to zero. All other real numbers are valid input values for this function. Therefore, the domain of the function y = (3/x) - 1 is all real numbers except x = 0. In interval notation, we can represent the domain as (-∞, 0) ∪ (0, ∞).
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At Olivia's Hats, 90% of the 80 hats are baseball caps. How many baseball caps are there?
can yall awnser this asap pls I NEED TO PASS!!
Answer: 36 inches
Step-by-step explanation:
The lateral surface area of a cube with sides of length 3 inches is given by the sum of the areas of all four side faces. Each side face is a square with an area equal to the product of the length and width, which in this case is 3 inches by 3 inches. Therefore, the lateral surface area of the cube is:
LSA = 4 x (3 inches x 3 inches) = 36 square inches
So the lateral surface area of the cube is 36 square inches
Which linear equation represents a relation that is NOT a function? y = 3x +6 y = 9 −4y + 5x = 20 x = 7
Answer:
x = 7 is not a function--it is a vertical line.
In a box of nerds candy, the ratio of pink to purple candies is 19:20. if there are 429 pieces of candy in the box, how many are pink?
There are 199 pink candies in the box of Nerds calculated on the basis of given information.
To find out, you first need to add the ratio of pink and purple candies, which is 19+20=39. Then, divide the total number of candies by the sum of the ratio to find the value of one unit of the ratio, which is 429/39 = 11.
Then, multiply the value of one unit of the ratio by the value of the pink candies, which is 19, to find the number of pink candies, which is 11 x 19 = 209. Therefore, there are 209 purple candies in the box.
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How to work out the size of angle x with 35° degrees only
Answer:
Step-by-step explanation:
33
A spotlight is mounted on the eaves of a house 20 feet above the ground. A flower bed runs between the house and the sidewalk, so the closest the ladder can be placed to the house is 15 feet. How long a ladder is needed so that an electrician can reach the place where the light is mounted
Answer:
Step-by-step explanation:
We can use the Pythagorean theorem to solve this problem. Let's call the length of the ladder "L". The ladder, the wall of the house, and the ground form a right triangle. The distance between the ladder and the house is the base of the triangle, which is 15 feet. The height of the triangle is the distance from the ground to the spotlight, which is 20 feet. The length of the ladder is the hypotenuse of the triangle.
Using the Pythagorean theorem, we have:
L^2 = 15^2 + 20^2
L^2 = 225 + 400
L^2 = 625
L = sqrt(625)
L = 25
Therefore, a ladder of at least 25 feet is needed for the electrician to reach the place where the light is mounted.