(60-2x)(40-2x)=2016

Solution for (60-2x)(40-2x)=2016 equation:

(60-2x)(40-2x)=2016

We move all terms to the left:

(60-2x)(40-2x)-(2016)=0

We add all the numbers together, and all the variables

(-2x+60)(-2x+40)-2016=0

We multiply parentheses ..

(+4x^2-80x-120x+2400)-2016=0

We get rid of parentheses

4x^2-80x-120x+2400-2016=0

We add all the numbers together, and all the variables

4x^2-200x+384=0

a = 4; b = -200; c = +384;
Δ = b2-4ac
Δ = -2002-4·4·384
Δ = 33856
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{33856}=184$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-200)-184}{2*4}=\frac{16}{8}
=2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-200)+184}{2*4}=\frac{384}{8}
=48
$