100r^2+5=69

Solution for 100r^2+5=69 equation:

100r^2+5=69

We move all terms to the left:

100r^2+5-(69)=0

We add all the numbers together, and all the variables

100r^2-64=0

a = 100; b = 0; c = -64;
Δ = b2-4ac
Δ = 02-4·100·(-64)
Δ = 25600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{25600}=160$
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-160}{2*100}=\frac{-160}{200}
=-4/5
$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+160}{2*100}=\frac{160}{200}
=4/5
$