80=75y^2+734y

Solution for 80=75y^2+734y equation:

80=75y^2+734y

We move all terms to the left:

80-(75y^2+734y)=0

We get rid of parentheses

-75y^2-734y+80=0

a = -75; b = -734; c = +80;
Δ = b2-4ac
Δ = -7342-4·(-75)·80
Δ = 562756
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{562756}=\sqrt{4*140689}=\sqrt{4}*\sqrt{140689}=2\sqrt{140689}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-734)-2\sqrt{140689}}{2*-75}=\frac{734-2\sqrt{140689}}{-150}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-734)+2\sqrt{140689}}{2*-75}=\frac{734+2\sqrt{140689}}{-150}
$