answer and give proof and ill give brainliest

Answer:

1) x- y = 8

x + y = 12

eliminate one variable by adding the equations

2x = 20

divided by 2 on both sides

x = 10

substitute the value of x in the equation 1

10 - y = 8

-y = 8- 10

y =2

[x , y]

[10 , 2]

2) 2x - y = 4

3x + y = 6

eliminate one variable by adding the equations

5x = 10

x = 2

substitute the value of x in the equation

2(2) - y = 4

4 - y = 4

y = 0

[x ; y]

[2; 0]

3) x + 2y = 10

x + 4y = 14

multiply equation 1 by - 1

-x -2y = -10

x + 4y = 14

eliminate one variable by adding the equations

2 y = 4

y = 2

substitute the value of y in the equation 1

x + 2(2) = 10

x + 4 = 10

x = 6

[x ; y]

[6 ; 2]

4 ) 3x + y = 9

y = 3x + 6

simplify the expression

3x + y = 9

- 3x + y = 6

eliminate one variable by adding the equations

2y = 15

y = 15/2

substitute the value of y in equation 1

3x + 15/ 2 = 9

3x = 3/2

x = 1/2

[x ; y]

[1/2 ; 15/ 2]

5) 4x + 5y = 15

6x - 5y = 18

eliminate one variable by adding the equations

10 x = 33

× = 33/10

substitute the value of x in equation I

4 (33/10) + 5y = 15

66/5 + 5y =15

5y = 9/5

y = 9/25

[x ; y]

[33/10 ; 9/25]

6) 5x = 7y

x + 7y = 21

in equation I move the variable to the left

5x - 7y = 0

x + 7 y = 21

eliminate one variable by adding the equations

6x = 21

x = 7/2

substitute the value of x in the equation

5(7/2) = 7y

35/2 = 7y

5/2 = y

[x ; y ]

[7/2 ; 5/2 ]

Answer:

The answer is 23 chocolates

Step-by-step explanation:

You do 5 times 5 for her eating 5 chocolates a day for 5 days to get 25 and then you take 48 and subtract it by 25 and you get 23

Answer:

a) 0.1587 = 15.87% probability that a battery will break down during the warranty period.

b) The expected profit of the auto store on a battery is of $15.239.

c) The expected monthly profit on batteries if the auto store sells an average of 500 batteries a month is of $7,619.50.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

The life of batteries is known to be normally distributed with a mean and a standard deviation of 40 and 16 months, respectively.

This means that [tex]\mu = 40, \sigma = 16[/tex]

a. What is the probability that a battery will break down during the warranty period?

Two year warranty, that is, 24 months. This probability is the pvalue of Z when X = 24. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{24 - 40}{16}[/tex]

[tex]Z = -1[/tex]

[tex]Z = -1[/tex] has a pvalue of 0.1587.

0.1587 = 15.87% probability that a battery will break down during the warranty period.

b. What is the expected profit of the auto store on a battery?

1 - 0.1587 = 0.8413 probability of a profit of $20.

0.1587 probability of a loss of $10. So

[tex]E = 0.8413*20 - 0.1587*10 = 15.239[/tex]

The expected profit of the auto store on a battery is of $15.239.

c. What is the expected monthly profit on batteries if the auto store sells an average of 500 batteries a month?

Multiplying the average for a battery by 500. So

15.239*500 = $7,619.50

The expected monthly profit on batteries if the auto store sells an average of 500 batteries a month is of $7,619.50.

Answer:

≈4776

Step-by-step explanation:

r=78/2

r=39

A=3.14r^2

A=3.14(39)^2

A=3.14*1521

A≈4776

Hope this helps :)

Answer:

Imma guess around 350 cubic inches

Step-by-step explanation:

I'm just going off of my hand compared to my basketball

Answer:

About 433.526 inches^3

Step-by-step explanation:

Goal: Calculate the volume of a Basketball as accurately as possible. Objective 1: Calculate the volume of a basketball.

Step One: Find the radius of the basket ball inflated at 8 PSI. To do this we used a string to measure the circumference of the basket ball arriving at a measurement of 29 inches. Next we inserted that number into the formula C = 2πR where C= circumference and R= Radius. We found that where C= 29inches, R= 4.615 inches.

Solve with Volume of a ball or sphere = 4/3*pi*radius

Answer:

(gof)(x) = x² + 2x + 1

Step-by-step explanation:

You can solve this by plugging  f into g and finding the result:

(gof)(x) = f(x)²

= (x + 1)²

= x² + 2x + 1

Answer:

160pi

Step-by-step explanation:

the volume of a cylinder is found using the formula V=pi x r² x h. taking r=4 this means we have pi x 16 x10 =160pi

Answer:

Yes you can.

Step-by-step explanation:

Multiply length x width.

Other:

If you want me to find the exact answer, it is not currently possible as you haven't given me any dimensions.

Answer:

D

Step-by-step explanation:

This is a pythagoream thereom question, the area of a square can be found by multiplying the sides. All the sides of a sqaure are the same so we are basically sqauring the side lengths. That is where the [tex]BE^{2}[/tex] and [tex]BH^{2}[/tex] come from. The problem tells us that the area of the two small squares are equal to the one bigger square. And the area of the bigger sqaure can be found by squaring that side EH. So [tex]BE^{2}[/tex]+[tex]BH^{2} =EH^{2}[/tex].

Answer:

I think it's A, if you just subtract 25 from each top # you should get the right one

edit; yah it's A

Answer:

B is the correct answer

Step-by-step explanation:

Look at the graph. For every day, there should be 25 less containers of peanuts than popcorns. Let X represent popcorns. Everyday, X - 25 should be your amount of peanut containers.

Only A and B works, so now just add the total amount of containers for both peanuts and popcorns.

225 + 200 + 150 + 300 + 200 + 175 + 125 + 275 = 1650

Only B matches the description of 1650 total containers. So, B is your answer.

Answer:

Step-by-step explanation:

The length of the strip is equal to perimeter of the kitchen.

Cost of the strip is:

An expression is defined as a set of numbers, variables, and mathematical operations. The correct option is C.

In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations formed according to rules dependent on the context.

The perfect square of the given expression can be created by adding 36 to the expression, then the expression will reduce to,

(x-6)² = x² - 12x + 36

Hence, the correct option is C.

Learn more about Expression:

https://brainly.com/question/13947055

#SPJ1

Answer:

ok

Step-by-step explanation:

I think

Answer:

M < or = -20

Step-by-step explanation:

Brainlist please

Answer:

Step-by-step explanation:

36x^3 - 81x

9x(4x^2 - 9)

9x(2x - 3)(2x + 3)

She is right

Answer:

Option c is correct

Step-by-step explanation:

Hope it helps✌

Answer:

9.4

3rd option

The boats are 9.4 units apart.

Answer:

A) Yes; AA Similarity

Step-by-step explanation:

Yes; AA Similarity

Answer:

Add -62 and 4

Step-by-step explanation:

Step-by-step explanation:

-62+4=-20

-58=-20

58=20

Answer:

∠GHJ and ∠FEC

Step-by-step explanation:

Alternate exterior angles are two angles that lie on the outer part of the parallel lines but on different sides.

∠GHJ and ∠FEC lie on the outer parts of the parallel lines, but different sides.

∠GHJ is on the lower left side.

∠FEC is on the upper right side.

Answer:

i think the answer is 105.96

Answer:

the markup percentage is 66.67%

Step-by-step explanation:

The computation of the percent of markup based on cost is shown below:

= (Selling price - paid price) ÷ (paid price)

= ($15 - $9) ÷ ($9)

= 66.67%

By taking the difference of the selling price & paid price and then divided it by paid price we can get the percentage of markup

Hence, the markup percentage is 66.67%

Answer:

d

Step-by-step explanation:

please mark as brainliest if correct

thank you

have a great day/night

:)

Answer:

Four tenths

Step-by-step explanation:

You are correct. The dot is on 0.4. the 4 is in the tenths place, so four tenths.

Answer:

45.3 miles/h

Step-by-step explanation:

let 'x' be the speed of the car.

60 × 2/3 = 120/3 = 40  

30 × 1/5 = 151/5  

151/5 /40 = x / 60  

151 / 200 = x / 60

=> x = (151×60) / 200

=> x = 45.3

(hope this helps can i plz have brainlist :D hehe)

Answer:

45

Step-by-step explanation:

9x10/2=45

Answer:

C) It will not change

Hope this helps! :)

9514 1404 393

Answer:

  y = 6

Step-by-step explanation:

Let's call the marked angles A, B, C, clockwise from upper left.

Along the vertical transversal, we observe that A+90° and C are alternate exterior angles, so are congruent. This lets us find a value for x.

  A+90 = C

  4x +90 = 11x -8

  98 = 7x

  14 = x

Then angle A is ...

  A = 4x° = 4(14)° = 56°

__

Along the horizontal transversal, we observe that A and B are alternate exterior angles, so are congruent. This lets us find a value for y.

  A = B

  56° = (9y +2)°

  54 = 9y

  6 = y

The value of y is 6.

Answer:

x = 27.2

Step-by-step explanation:

Apply trigonometric function to solve for x.

Reference angle = 54°

Side length opposite to reference angle = 22

Hypotenuse = x

We would apply SOH:

Sin 54 = Opp/Hyp

Sin 54 = 22/x

x*sin 54 = 22

x = 22/sin 54

x = 27.1934955 ≈ 27.2 (nearest tenth)