(240+x)(375+x)=90000

Solution for (240+x)(375+x)=90000 equation:

(240+x)(375+x)=90000

We move all terms to the left:

(240+x)(375+x)-(90000)=0

We add all the numbers together, and all the variables

(x+240)(x+375)-90000=0

We multiply parentheses ..

(+x^2+375x+240x+90000)-90000=0

We get rid of parentheses

x^2+375x+240x+90000-90000=0

We add all the numbers together, and all the variables

x^2+615x=0

a = 1; b = 615; c = 0;
Δ = b2-4ac
Δ = 6152-4·1·0
Δ = 378225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{378225}=615$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(615)-615}{2*1}=\frac{-1230}{2}
=-615
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(615)+615}{2*1}=\frac{0}{2}
=0
$