4(x^2-8x-425)=0

Solution for 4(x^2-8x-425)=0 equation:

4(x^2-8x-425)=0

We multiply parentheses

4x^2-32x-1700=0

a = 4; b = -32; c = -1700;
Δ = b2-4ac
Δ = -322-4·4·(-1700)
Δ = 28224
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{28224}=168$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-32)-168}{2*4}=\frac{-136}{8}
=-17
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-32)+168}{2*4}=\frac{200}{8}
=25
$