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yulyashka [42]
3 years ago
6

What is the value of 4r^2-8 when r=3?

Mathematics
2 answers:
Vlad [161]3 years ago
5 0

Answer:

28

Step-by-step explanation:

So this means to replace the r you see in 4r^2-8 with 3.

Let's do that:

4(3)^2-8

Now to simplify this just use pemdas or a calculator:

4(9)-8     since 3^2 means 3*3=9

36-8

28

Olin [163]3 years ago
5 0

Answer:

28.

Step-by-step explanation:

Put r =- 3 and work it out:

That would be 4(3)^2 - 8

=  4 * 9 - 8

= 36 - 8

= 28.

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Similar triangles ... help?
jolli1 [7]

Answer:

The second answer

XYZ-RQS

Step-by-step explanation:

8 0
3 years ago
ok so if you have 3 and 1/4 pizza and want to subtract 3/4 out of it,and get 3x more slices then you had from a friend after sub
Brilliant_brown [7]

Answer:

You have 2 and 1/2 pizzas and your friend has 5/6 of a pizza.

Step-by-step explanation:

You have 3 1/4 pizzas. If you get rid of 3/4 of a pizza, you will end up with 2 2/4 pizzas.

To make it easier, you can just change the values into improper fractions: 3 1/4 = 13/4

13/4 - 3/4 = 10/4

10/4 = 2 2/4 pizzas

(2 2/4 = 2 1/2)

Anyways! You now have 2 and a half pizzas. You have 3 times the amount of pizza that your friend has. In other words, your friend has 1/3 the amount of pizza that you have. You can solve for this in two ways, whichever way you solve it is up to you.

  1. You can solve this problem by dividing the amount of food you have by 3: \frac{2\frac{1}{2} }{3} which equals 0.8333... (the 3 is repeating). But you can just keep your final answer in fraction form if you want to: \frac{2.5}{3} = \frac{5}{6}
  2. You can solve this problem by multiplying 1/3 to the amount of food you have: \frac{1}{3} * 2 \frac{2}{4}\\=\frac{10}{12}\\ =\frac{5}{6}

You have 2 and 1/2 pizzas and your friend has 5/6 of a pizza.

8 0
2 years ago
16. Find the length of the median CD.
hodyreva [135]

Step-by-step explanation:

16. Length of a line = sqaureroot of ((x1-x0)^2 - (y1- y0)^2)

C (2,-3) D (6,3)

CD = sqaureroot of ((6-2)^2 + (3-(-3))^2)

CD = sqaureroot of ( 16 + 36)

CD = sqaureroot of 52 = 2 root 13 = length

17. E (5, - 1) because the point is under the x axis.

Midpoint = ((x1+ x0)/2 , (y1 +y0) /2)

B (8,1) C (2, - 3)

Midpoint of BC = ((2+8)/2 , (-3+1)/2)

= (10/2 , - 2/2)

= (5, - 1)

18. Length of AE

A (4,5) E(5,-1)

Square root of ((5-4)^2 + (-1-5)^2)

Square root of (1^2 + - 6^2)

Square root of ( 1 + 36)

Square root of 37 = root 37

Please gimme brainliest

7 0
2 years ago
Which of the following is the surface area of the right cylinder below?
yarga [219]

Answer:

if it is TSA- 396 or 395.64

if it is CSA- 88 or 87.92

Step-by-step explanation:

r=7

h=2

TSA= 2 pi r(r+h)

=2*22/7*7*9= 396

<em>CSA</em>= 2 pi r h

2*22/7*7*2=88

when you use pi as 3.14 instead of 22/7 you get the answer with the decimal symbol.. in such case the TSA would be 395.64 and CSA would be 87.92

6 0
3 years ago
Read 2 more answers
The transversal is crossing two parallel lines. Find the value of x.
ira [324]

Answer:

x=32

Step-by-step explanation:

5x+20=180 can be used to solve this problem because those two angles are supplementary

5 0
3 years ago
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