525=x2-4x-(2x-4x)

Solution for 525=x2-4x-(2x-4x) equation:

525=x2-4x-(2x-4x)

We move all terms to the left:

525-(x2-4x-(2x-4x))=0

We add all the numbers together, and all the variables

-(x2-4x-(-2x))+525=0


We calculate terms in parentheses: -(x2-4x-(-2x)), so:

x2-4x-(-2x)

We add all the numbers together, and all the variables

x^2-4x-(-2x)

We get rid of parentheses

x^2-4x+2x

We add all the numbers together, and all the variables

x^2-2x

Back to the equation:

-(x^2-2x)


We get rid of parentheses

-x^2+2x+525=0

We add all the numbers together, and all the variables

-1x^2+2x+525=0

a = -1; b = 2; c = +525;
Δ = b2-4ac
Δ = 22-4·(-1)·525
Δ = 2104
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:

$\sqrt{\Delta}=\sqrt{2104}=\sqrt{4*526}=\sqrt{4}*\sqrt{526}=2\sqrt{526}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(2)-2\sqrt{526}}{2*-1}=\frac{-2-2\sqrt{526}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+2\sqrt{526}}{2*-1}=\frac{-2+2\sqrt{526}}{-2}
$