x^2-7x=800

Solution for x^2-7x=800 equation:

x^2-7x=800

We move all terms to the left:

x^2-7x-(800)=0

a = 1; b = -7; c = -800;
Δ = b2-4ac
Δ = -72-4·1·(-800)
Δ = 3249
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3249}=57$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-7)-57}{2*1}=\frac{-50}{2}
=-25
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-7)+57}{2*1}=\frac{64}{2}
=32
$