3.14(r^2)/2=12

Solution for 3.14(r^2)/2=12 equation:

3.14(r^2)/2=12

We move all terms to the left:

3.14(r^2)/2-(12)=0

We multiply all the terms by the denominator


3.14r^2-12*2=0

We add all the numbers together, and all the variables

3.14r^2-24=0

a = 3.14; b = 0; c = -24;
Δ = b2-4ac
Δ = 02-4·3.14·(-24)
Δ = 301.44
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{301.44}}{2*3.14}=\frac{0-\sqrt{301.44}}{6.28}
=-\frac{\sqrt{}}{6.28}
$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{301.44}}{2*3.14}=\frac{0+\sqrt{301.44}}{6.28}
=\frac{\sqrt{}}{6.28}
$