750=x^2+5x

Solution for 750=x^2+5x equation:

750=x^2+5x

We move all terms to the left:

750-(x^2+5x)=0

We get rid of parentheses

-x^2-5x+750=0

We add all the numbers together, and all the variables

-1x^2-5x+750=0

a = -1; b = -5; c = +750;
Δ = b2-4ac
Δ = -52-4·(-1)·750
Δ = 3025
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3025}=55$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-5)-55}{2*-1}=\frac{-50}{-2}
=+25
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-5)+55}{2*-1}=\frac{60}{-2}
=-30
$