375=(50-2x)(30-2x)

Solution for 375=(50-2x)(30-2x) equation:

375=(50-2x)(30-2x)

We move all terms to the left:

375-((50-2x)(30-2x))=0

We add all the numbers together, and all the variables

-((-2x+50)(-2x+30))+375=0

We multiply parentheses ..

-((+4x^2-60x-100x+1500))+375=0


We calculate terms in parentheses: -((+4x^2-60x-100x+1500)), so:

(+4x^2-60x-100x+1500)

We get rid of parentheses

4x^2-60x-100x+1500

We add all the numbers together, and all the variables

4x^2-160x+1500

Back to the equation:

-(4x^2-160x+1500)


We get rid of parentheses

-4x^2+160x-1500+375=0

We add all the numbers together, and all the variables

-4x^2+160x-1125=0

a = -4; b = 160; c = -1125;
Δ = b2-4ac
Δ = 1602-4·(-4)·(-1125)
Δ = 7600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{7600}=\sqrt{400*19}=\sqrt{400}*\sqrt{19}=20\sqrt{19}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(160)-20\sqrt{19}}{2*-4}=\frac{-160-20\sqrt{19}}{-8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(160)+20\sqrt{19}}{2*-4}=\frac{-160+20\sqrt{19}}{-8}
$