-8x2=12x-20

Solution for -8x2=12x-20 equation:

-8x^2=12x-20

We move all terms to the left:

-8x^2-(12x-20)=0

We get rid of parentheses

-8x^2-12x+20=0

a = -8; b = -12; c = +20;
Δ = b2-4ac
Δ = -122-4·(-8)·20
Δ = 784
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{784}=28$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-28}{2*-8}=\frac{-16}{-16}
=1
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+28}{2*-8}=\frac{40}{-16}
=-2+1/2
$