121r^2=64

Solution for 121r^2=64 equation:

121r^2=64

We move all terms to the left:

121r^2-(64)=0

a = 121; b = 0; c = -64;
Δ = b2-4ac
Δ = 02-4·121·(-64)
Δ = 30976
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{30976}=176$
$r_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-176}{2*121}=\frac{-176}{242}
=-8/11
$
$r_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+176}{2*121}=\frac{176}{242}
=8/11
$