36r^2-4=5

Solution for 36r^2-4=5 equation:

36r^2-4=5

We move all terms to the left:

36r^2-4-(5)=0

We add all the numbers together, and all the variables

36r^2-9=0

a = 36; b = 0; c = -9;
Δ = b2-4ac
Δ = 02-4·36·(-9)
Δ = 1296
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1296}=36$
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-36}{2*36}=\frac{-36}{72}
=-1/2
$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+36}{2*36}=\frac{36}{72}
=1/2
$