X(2x-12)=80

Solution for X(2x-12)=80 equation:

X(2X-12)=80

We move all terms to the left:

X(2X-12)-(80)=0

We multiply parentheses

2X^2-12X-80=0

a = 2; b = -12; c = -80;
Δ = b2-4ac
Δ = -122-4·2·(-80)
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*2}=\frac{-16}{4}
=-4
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+28}{2*2}=\frac{40}{4}
=10
$