8x^2+80x+72=0

Solution for 8x^2+80x+72=0 equation:

8x^2+80x+72=0

a = 8; b = 80; c = +72;
Δ = b2-4ac
Δ = 802-4·8·72
Δ = 4096
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4096}=64$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(80)-64}{2*8}=\frac{-144}{16}
=-9
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(80)+64}{2*8}=\frac{-16}{16}
=-1
$