x*x+5*x=750

Solution for x*x+5*x=750 equation:

x*x+5x=750

We move all terms to the left:

x*x+5x-(750)=0

We add all the numbers together, and all the variables

5x+x*x-750=0

Wy multiply elements

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