180=x^2+4x-7x-28

Solution for 180=x^2+4x-7x-28 equation:

180=x^2+4x-7x-28

We move all terms to the left:

180-(x^2+4x-7x-28)=0

We get rid of parentheses

-x^2-4x+7x+28+180=0

We add all the numbers together, and all the variables

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