(x)(x+15)(5)=2250

Solution for (x)(x+15)(5)=2250 equation:

(x)(x+15)(5)=2250

We move all terms to the left:

(x)(x+15)(5)-(2250)=0

We multiply parentheses

5x^2+75x-2250=0

a = 5; b = 75; c = -2250;
Δ = b2-4ac
Δ = 752-4·5·(-2250)
Δ = 50625
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{50625}=225$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(75)-225}{2*5}=\frac{-300}{10}
=-30
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(75)+225}{2*5}=\frac{150}{10}
=15
$