The area of a square is 49cm^2. The perimeter of the square is equal to the circumference of a circle. what is the radius of the circle?
This is a geometry question.
We know that a square has 4 equal sides of x, and that it's area is given by A=x2.
So we can work out the length of the side of the square.
x=sqrt(49) = 7
We are told this is equal to the circumference of the circle.
The equation for circumference of a circle is, c=2πr
We need to find r, so we can rearrange this to give; r = c / 2π
Substituting in the value for c =49 cm
we get r = 49 / 2π = 7.80 cm
*Don't forget units!
JC
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