x^2-3x-28=180

Solution for x^2-3x-28=180 equation:

x^2-3x-28=180

We move all terms to the left:

x^2-3x-28-(180)=0

We add all the numbers together, and all the variables

x^2-3x-208=0

a = 1; b = -3; c = -208;
Δ = b2-4ac
Δ = -32-4·1·(-208)
Δ = 841
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{841}=29$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-3)-29}{2*1}=\frac{-26}{2}
=-13
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3)+29}{2*1}=\frac{32}{2}
=16
$