Question

A circle whose area is 4 has a radius of x find the area of a circle whose radius is 3x

Answer 1

The first one is 1.12867 because you need to set it up like this.
4=3.14(x)squared
4/3.14=x(squared)
x=1.12867

The second one is done simply by multiplying it out.
A=3.14(3x)squared
A=3.14(9x[squared])
A=28.26x[squared]        -The squared is referring to the x.

Answer 2

Answer:

Area =  36 units.

Step-by-step explanation:

Given  : A circle whose area is 4 has a radius of x .

To find : find the area of a circle whose radius is 3x.

Solution: We have given

Area of circle = 4 units.

Radius = x .

Formula of area = pi (radius)².

Plug the values

pi (x)² = 4 -------(A)

If the radius = 3x .

Then 4

Area =  pi (3x)².

Area = pi (9)(x)².

Area = 9 pi (x)²-----(B) .

We can see from equation ( A)  4 = pi (x)²

Area = 9 * 4.

Area =  36 units.

Therefore, Area =  36 units.