Question

Solve the area formula for a circle, A = πr2, for r2.

r2 = Aπ

r2 = A – π

Answer 1

The solution of r² is r² =
`(A)/(\pi )`

Explanation:

To solve an equation for one of its variables, do that

1. Separate the term of this variable on one side and the other terms on the other sides
2. Make the coefficient of the variable equals1 (if it is not 1)

Let us solve the question

∵ The formula of the area of the circle is A = π r²

∵ The subject is r² ⇒ The variable which we need to solve for it

→ By using the 1st step up divide both sides by π to move it from the right

side to the left side

∵
`(A)/(\pi )` =
`(\pi r^(2))/(\pi )`

∴
`(A)/(\pi )` = r²

→ Switch the two sides

∴ r² =
`(A)/(\pi )`