8x^2+96x=-280

Solution for 8x^2+96x=-280 equation:

8x^2+96x=-280

We move all terms to the left:

8x^2+96x-(-280)=0

We add all the numbers together, and all the variables

8x^2+96x+280=0

a = 8; b = 96; c = +280;
Δ = b2-4ac
Δ = 962-4·8·280
Δ = 256
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{256}=16$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(96)-16}{2*8}=\frac{-112}{16}
=-7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(96)+16}{2*8}=\frac{-80}{16}
=-5
$