5x-2x(x-5)=4

Solution for 5x-2x(x-5)=4 equation:

5x-2x(x-5)=4

We move all terms to the left:

5x-2x(x-5)-(4)=0

We multiply parentheses

-2x^2+5x+10x-4=0

We add all the numbers together, and all the variables

-2x^2+15x-4=0

a = -2; b = 15; c = -4;
Δ = b2-4ac
Δ = 152-4·(-2)·(-4)
Δ = 193
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(15)-\sqrt{193}}{2*-2}=\frac{-15-\sqrt{193}}{-4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+\sqrt{193}}{2*-2}=\frac{-15+\sqrt{193}}{-4}
$