7x2-40x-528=0

Solution for 7x2-40x-528=0 equation:

7x^2-40x-528=0

a = 7; b = -40; c = -528;
Δ = b2-4ac
Δ = -402-4·7·(-528)
Δ = 16384
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16384}=128$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-40)-128}{2*7}=\frac{-88}{14}
=-6+2/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-40)+128}{2*7}=\frac{168}{14}
=12
$