3.14*r^2=60.7904

Solution for 3.14*r^2=60.7904 equation:

3.14r^2=60.7904

We move all terms to the left:

3.14r^2-(60.7904)=0

We add all the numbers together, and all the variables

3.14r^2-60.7904=0

a = 3.14; b = 0; c = -60.7904;
Δ = b2-4ac
Δ = 02-4·3.14·(-60.7904)
Δ = 763.527424
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-\sqrt{763.527424}}{2*3.14}=\frac{0-\sqrt{763.527424}}{6.28}
=-\frac{\sqrt{}}{6.28}
$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{763.527424}}{2*3.14}=\frac{0+\sqrt{763.527424}}{6.28}
=\frac{\sqrt{}}{6.28}
$