8x^2-32x-1140=-20

Solution for 8x^2-32x-1140=-20 equation:

8x^2-32x-1140=-20

We move all terms to the left:

8x^2-32x-1140-(-20)=0

We add all the numbers together, and all the variables

8x^2-32x-1120=0

a = 8; b = -32; c = -1120;
Δ = b2-4ac
Δ = -322-4·8·(-1120)
Δ = 36864
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36864}=192$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-32)-192}{2*8}=\frac{-160}{16}
=-10
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-32)+192}{2*8}=\frac{224}{16}
=14
$