i don’t know the answer and need help

1) (-5, 5), 2) (7, -5), 3) (- 3, 28), 4) (- 12, 0), 5) 10, 6) 14, 7) (- 9, 9), 8) [tex]\sqrt{26}[/tex], 9) - 2, 10) 10, 11) [tex]\left(\frac{\sqrt{26}}{26}, \frac{5\sqrt{26}}{26}\right)[/tex], 12) [tex]\left(\frac{21\sqrt{10}}{10}, -\frac{7\sqrt{10}}{10} \right)[/tex], 13) (0, 7), 14) [tex](- 3\sqrt{3}, - 3)[/tex], 15) The vectors [tex]\vec a[/tex] and [tex]\vec b[/tex] are orthogonal, 16) [tex]7\sqrt{2}[/tex], [tex]135^{\circ}[/tex], 17) [tex]17[/tex], [tex]137^{\circ}[/tex], 18) [tex]12[/tex], [tex]240^{\circ}[/tex], 19) [tex](19.700, 15.392)[/tex]

Vectors are elements that are charaterized for having a magnitude and a direction, whereas scalar are only characterized by magnitude. In this question we must apply different vector properties to obtain the corresponding results.

The first two exercises consist in calculating each vector based on its initial and terminal points, whose results are obtained below by sum of vectors with initial points at origin:

1) (-1, 3) - (4, -2) = (-5, 5)

2) (2, -6) - (- 5, -1) = (7, -5)

The following eight exercises are resolved by applying the operations of addition of vectors and multiplication of a vector by a scalar, and the definition of norm and dot product as well:

3) 3 · (3, 4) + 2 · (- 6, 8) = (9, 12) + (- 12, 16) = (- 3, 28)

4) (- 6, 8) - 2 · (3, 4) = (- 12, 0)

5) [tex]\| \vec v\| = \sqrt{(-6)^{2}+8^{2}}[/tex] = 10

6) [tex]\vec u \,\bullet \,\vec v =[/tex] 3 · (- 6) + 4 · 8 = 14

7) 3 · [(0, 2) - (3, -1)] = 3 · (- 3, 3) = (- 9, 9)

8) [tex]\|\vec v\| = \sqrt{1^{2}+5^{2}} = \sqrt{26}[/tex]

9) [tex]\vec u \,\bullet \,\vec v =[/tex] 3 · 1 + (- 1) · 5 = - 2

10) [tex]\vec w \,\bullet \, \vec v =[/tex] 0 · 1 + 5 · 2 = 10

11) The unit vector is obtained by dividing the vector by its magnitude:

[tex]\vec u_{v} = \frac{1}{\sqrt{26}}\cdot \left(1, 5\right) = \left(\frac{1}{\sqrt{26}}, \frac{5}{\sqrt{26}} \right) = \left(\frac{\sqrt{26}}{26}, \frac{5\sqrt{26}}{26}\right)[/tex]

12) The vector is equal to the product of the magnitude and its unit vector:

[tex]\vec r = 7 \cdot \frac{\vec u}{\|\vec u\|}[/tex]

[tex]\vec r = \frac{7}{\sqrt{10}}\cdot (3, -1) = \left(\frac{21}{\sqrt{10}}, -\frac{7}{\sqrt{10}} \right) = \left(\frac{21\sqrt{10}}{10}, -\frac{7\sqrt{10}}{10} \right)[/tex]

13) and 14) The vector is the product of the magnitude and the directional vector:

13) [tex]\vec r = 7 \cdot (\cos 90^{\circ}, \sin 90^{\circ}) = (0, 7)[/tex]

14) [tex]\vec r = 6\cdot (\cos 210^{\circ}, \sin 210^{\circ}) = (- 3\sqrt{3}, - 3)[/tex]

15) Two vectors are orthogonal if and only if their dot product is zero:

[tex](3.2, 4.8) \,\bullet\,(-3, 2) =[/tex] 3.2 · (- 3) + 4.8 · 2 = 0

The vectors [tex]\vec a[/tex] and [tex]\vec b[/tex] are orthogonal.

The next three exercises are resolved by definitions of norm and direction:

16) [tex]\|\vec v\| = \sqrt{(-7)^{2}+7^{2}} = 7\sqrt{2}[/tex], [tex]\theta = 135^{\circ}[/tex]

17) [tex]\|\vec v\| = 17[/tex], [tex]\theta = 137^{\circ}[/tex]

18) [tex]\|\vec q\| = 12[/tex], [tex]\theta = 240^{\circ}[/tex]

The last exercise consist in defining the vector as a product of magnitude and direction vector:

19) [tex]\vec v = 25\cdot (\cos 38^{\circ}, \sin 38^{\circ}) = (19.700, 15.392)[/tex]

To learn more on vectors, we kindly invite to check this verified question: https://brainly.com/question/13322477

Answer:

See below ~

Step-by-step explanation:

First 3 blanks

Final blank

Answer:

Step-by-step explanation:

Answer:

See below

Step-by-step explanation:

Feel free to be creative or even to come up with an activity you think your teacher has not seen before.

Liked that. So let's be creative.

Part 1: Record Information

Spend a short amount of time (one to five minutes) doing your activity. Answer the following questions:

1. What was the activity?

I am from Japan and practice Kendo (feel free to search about it). Suppose you are doing suburi. You did 100 joge suburi.

2. How long did you spend doing your activity?

Suppose it took you 5 minutes.

3. How much of the activity did you complete in the time period? (Example: I did 24 sit-ups in one minute.)

You did 100 joge suburi in 5 minutes. It means [tex]\frac{100}{5} =20[/tex] [tex]per[/tex] [tex]minute[/tex]

4. Which of these variables is your dependent variable?

If you want to calculate how much suburi you did in an amount of time , given the time in minutes, we can write the function

[tex]y=f(x)=20x[/tex]

Therefore, the dependent variable is the number of suburis. More precisely it is given by [tex]y[/tex]. On the other hand, the independent variable is [tex]x[/tex], the time.

Considering the example: I did 24 sit-ups in one minute.

sit-ups is the dependent variable and the number of minutes represents the independent variable.

Note: The number of sit-ups will depend on the time. 24 is the coefficient. In this case, the function would be

[tex]g(x)=24x[/tex]

5. Which one is the independent variable?

The time in minutes.

6. Write a sentence that describes the relationship between the dependent variable and the independent variable. (Hint: Ratio language can help.)

You can write: The ratio of suburi done is 100:5 or 20:1 because for every 1 minute passed you did 20 suburis.  

Part 2: Prepare a Table

Assuming that you could complete the activity at the same rate over different time periods, how much of the activity could you complete in two minutes, three minutes, four minutes, and five minutes? (Note: If you spent two minutes doing your activity, then you should edit the table below and use multiples of 2 up to 10).

You may use the table below for your variables.

Time (minutes)          Quantity of suburi

0                                         0

1                                          20

2                                         40

3                                         60

4                                          80

5                                         100

Part 3: Prepare a Graph

Create a graph to show your relationship. Make sure you include all the parts for a graph and show the data clearly. Include a title for the graph and label the x- and y-axes.

This part I will let it to your. But is is just a linear graph.

Part 4: Write an Equation

Based on your recorded values, write an equation that represents the relationship between the time you spent doing the activity and the amount of the activity you completed. Make sure to define your variables.

[tex]y=f(x)=20x,[/tex] ∀[tex]x[/tex] ∈ [tex]Z[/tex][tex]\geq_0[/tex]

[tex]y:[/tex] [tex]number[/tex] [tex]of[/tex] [tex]suburis[/tex]

[tex]x:[/tex] [tex]time[/tex]

7. If you were able to maintain this rate of your activity for 12 minutes, how much of the activity would you be able to complete?

For [tex]x=12[/tex]: [tex]y=f(12)=20*12=240[/tex]

240 suburis

8. How long would it take you to reach 100 for the number of times you did your activity?

5 minutes.

9. Which representation do you believe is the best way to share this information with someone else? This is your opinion. No answer is right or wrong.

The function is the best because it describes all the variables easily.

Answer: The second histogram a.k.a choice B is correct.

Answer:

$ 1.65 per gallon

Step-by-step explanation:

4 quarts in 1 gallon so 8 quarts in 2 gallons.

Cost for 2 gallons $13.20 so $13.20 ÷ 8 =  $1.65

Answer:

  3/7

Step-by-step explanation:

Write the division of the pizzas as a ratio, and you will have it.

  (3 pizzas)/(7 persons) = (3/7) pizza/person

__

Each person gets 3/7 of a pizza.

Answer:

PO

Step-by-step explanation:

Answer:

1/6

Step-by-step explanation: Im going to guess the dice has 6 sides, rolling any number on that 1 dice would be a 1/6 chance. I hope this helps!

Answer:

A

Step-by-step explanation:

The Y-intercept is -3.

The gradient is -3/4 since it goes down 3 every 4 tiles.

Answer:

[tex]y=-\frac{3}{4}x -3[/tex]

Step-by-step explanation:

Hey there!

We can form this equation in slope-intercept form

This means, we have to find the slope and the y intercept of the line

First lets find the slope

The equation for slope is [tex]\frac{y_{2}-y_{1}}{x_{2}-x_{1}}[/tex]

In order to find y and x, we need to take two points on the line

(-4, 0) and (0, -3)

x1   y1        x2  y2

Plug it in:

[tex]\frac{-3-0}{0-(-4)} \\\\\frac{-3}{4} \\\\-\frac{3}{4}[/tex]

This means, the slope is -3/4

Now we have to find the y-intercept

The y-intercept is where the line intercepts the y-axis

The line intercepts the y-axis at the point (0, -3)

So now that we have the slope and the y-intercept, we can form the equation

[tex]y=-\frac{3}{4}x-3[/tex]

Answer:

x=13

Step-by-step explanation:

<FGA is a vertical angle to <EGB, so both = to 77. Then since < CGB=90, we do 90-77=13

Answer:

16.260 (3 d.p.)

Step-by-step explanation:

Step-by-step explanation:

[tex]s = 20km \\ t = 30min[/tex]

[tex]v = \frac{s}{t} \\ v = \frac{2}{3} [/tex]

[tex]v = 0.67[/tex]

[tex]v = 0[/tex]

Answer: 4

Step-by-step explanation:

Answer:

The answer is C.

Step-by-step explanation:

C. 50-59 since it has the same number of employees as 10-19.

so he got for £95 and sold it for £133, so  hmmmm the difference is simply £38.

if we take 95 to be the 100%, what is 38 off of it in percentage?

[tex]\begin{array}{ccll} \pounds&\%\\ \cline{1-2} 95 & 100\\ 38& x \end{array} \implies \cfrac{95}{38}=\cfrac{100}{x}\implies \cfrac{5}{2}=\cfrac{100}{x} \\\\\\ 5x=200\implies x=\cfrac{200}{5}\implies x=40[/tex]

Answer:

42°

Step-by-step explanation:

Angles on one side of a straight line always add up to 180.

Therefore: 180° - 123° = 57°

So, 57° + 81° =138°

x=180° -138° = 42°

The probability of exactly 1 of the 4 marbles drawn being blue and at least 1 of the 4 marbles drawn being white will be 0.3535 and 0.7454 respectively.

Probability means possibility. It deals with the occurrence of a random event. The value of probability can only be from 0 to 1. Its basic meaning is something is likely to happen. It is the ratio of the favorable event to the total number of events.

Betty picks 4 random marbles from a bowl containing 3 white, 4 yellow, and 5 blue marbles.

The total number of the marbles will be

Total marble = 3 + 4 + 5

Total marble = 12

Then the probability of exactly 1 of the 4 marbles drawn being blue will be

[tex]\rm P(B) = \dfrac{^5C_1 \times ^7C_3}{^{12}C_4}\\\\P(B) = \dfrac{35}{99} = 0.353535[/tex]

Then the probability of at least 1 of the 4 marbles drawn being white will be

[tex]\rm P(W) = \dfrac{^{3}C_1\times \ ^{9}C_3}{^{12}C_4} + \dfrac{^{3}C_2\times \ ^{9}C_2}{^{12}C_4} + \dfrac{^{3}C_3\times \ ^{9}C_1}{^{12}C_4} \\\\\\P(W) = \dfrac{252}{495} + \dfrac{108}{495} + \dfrac{9}{495}\\\\\\P(W) = \dfrac{369}{495}\\\\\\P(W) = 0.745454[/tex]

More about the probability link is given below.

https://brainly.com/question/795909

Answer:

A. 0.3535.

B. 0.7455.

Step-by-step explanation:

The probability that exactly 1 of the 4 marbles drawn is blue is 0.3535. The probability that at least 1 of the 4 marbles drawn is white is 0.7455.

The arrival time in london of a train that leaves Leicester to london at 11:50 A.M is 13:05 pm.

To calculate the arrival time in london of a train that leaves Leicester to london at 11:50 A.M, use use the formula below.

Formula:

Where:

From the question,

Given:

Substitute these values into equation 1

Hence, the arrival time in london of a train that leaves Leicester to london at 11:50 A.M is 13:05 pm.

Learn more about time here: https://brainly.com/question/4931057

Answer:

There would be 5.5 or 5 1/2 classes

Step-by-step explanation:

Turn fractions into decimals

Multiply each by 60

Then Divide

Answer:

Less than

Step-by-step explanation:

1/3 * 7/15 is less than 1/3 because 1/3 * 7/15 is being multiplied by a number that is less than 1.

Divide 50 by 20%

50/20% = 50/0.20 = 250

Answer: 250

Answer:

maria: $2,500
henry:$750

Step-by-step explanation:

all you have to do is multiply them each by 6

Answer:

Maria will have $1500

Henry will have $750

Step-by-step explanation:

Maria - Multiply 250 x 6

Henry- Multiply 125 x 6

Answer:

4

Step-by-step explanation:

1/3 = x/12

12 * 1/3 =x      x = 4  

Answer:

[tex]4)\ = \frac{5}{\pi}[/tex]

Step-by-step explanation:

Formula:________________

circumference = Diameter × π

_______________________

Then

5 = Diameter × π

Then

[tex]Diameter \ = \frac{5}{\pi}[/tex]

Answer:

18 pi inches

Step-by-step explanation:

Circ of circle = pi * d

                      = 18 pi      exactly

Answer:

6.

Step-by-step explanation:

That is the number of permutations of 2 from 3

= 3P2

= 3!/(3-2(!

= 3*2

= 6.