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1 year ago

The area of a circle is 9pi cm². Find its radius. Please do this question with full solution:)

Mathematics

1 answer:

kirill115 [55]1 year ago

3 0

Answer:

3 cm

Step-by-step explanation:

The formula for the area of a circle is:

$A = \pi r^2$

Where "r" represents the radius of the circle. We can substitute the given value for Area into the equation to solve for the radius.

<h3>Solve for Radius</h3>

$A=\pi r^2\\9\pi = \pi r^2$

Divide both sides by π

$9=r^2$

Take the square root of both sides

$\sqrt9=\sqrt {r^2}\\r=3$

The radius of the circle is 3 cm.

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What is the length of the cylinder's height? Please help

raketka [301]

Answer:

Height = 9 cm which means Option C is the answer

Step-by-step explanation:

In the question we are given ,

Volume of cylinder = 225π cm³

Radius of cylinder = 5 cm

And , we have to find the height of cylinder .

We know that ,

$\longrightarrow \pink{ \boxed{Volume \: of \: Cylinder = \pi r {}^{2}h }} \longleftarrow$

Our solution starts from here :

$\longmapsto \: \pi \: r {}^{2} h = 225\pi$

Step 1 : Cancelling π with π :

$\longmapsto \: \cancel{\pi} \: r {}^{2} h = 225 \cancel{\pi}$

Step 2 : Substituting value of radius which is 5 cm in the formula :

$\longmapsto \: (5) {}^{2} \times h = 225$

$\longmapsto \: 25h = 225$

Step 3 : Transposing 25 to right hand side :

$\longmapsto \: h = \frac{225}{25}$

Step 4 : Cancelling 225 by 25 :

$\longmapsto \: \red{\boxed{h = 9 \: cm}}$

Henceforth , height of cylinder is 9 cm

<h2 /><h2>#Keep Learning</h2>

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2 years ago

Simplify your answer

DerKrebs [107]

Answer:

F(x) =-4(x+3)+5= - 4x-12+5= - 4x-7

Step-by-step explanation:

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2 years ago

Write an equation for each context. Draw a model first if necessary, and make sure you define your variable and what it represen

Bad White [126]

Answer:

(a)$2248.8

(b) 14, 28, 16 and 7 candies

Step-by-step explanation:

(a) the model can be represented by the nth term of an arithmetic progression

L = a + (n-1)d

L= the amount in his account after 6 month; $12484

a= the amount in his account six month before; $1240

n = 6, being the sixth month of his deposit

d = the amount deposited monthly

12484 = 1240 + 5d:

12484-1240 = 5d

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(b) let the 1st box contain = x

2nd = 2x; 3rd = x + 2, 4th = 1/4(2x)

Hence; x + 2x + x +2 + 1/4(2x) = 65

4x + x/2 = 65-2

9x/2 = 63 ; 9x = 126. ; x = 14

The 5 players get in all 5 racket + 5 cans since Simon is a member

Therefore, 5r + 5c = 415

But each can cost $4,

5r + 5* 4 = 415; 6r = 415-20

5r = 395 ; r = 395/5

r = $ 79

The racket cost $79 each.

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3 years ago

Eleven plus forty-one is divided by a number. If the result is 13, what's the number?

sergij07 [2.7K]

Answer:

Step-by-step explanation:

Let the number be x.

(11+41)/x = 13

52/x = 13

13x = 52

x = 52/13

x = 4

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3 years ago

If 50% of a number is 170 and 85% of the same number is 289, find 35% of that number.

kupik [55]

The answer to it is 119

since 50% of the number is 170 just multiply 170 by 2 to get 340, then find 35% of 340. 10% of 340 is 34, multiply 34 by 3.5 to get 119.

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1 year ago

The area of a circle is 9pi cm². Find its radius. Please do this question with full solution:)​

The area of a circle is 9pi cm². Find its radius. Please do this question with full solution:)