-2x(20-8x)-(15-5x)=(4x-5)

Solution for -2x(20-8x)-(15-5x)=(4x-5) equation:

-2x(20-8x)-(15-5x)=(4x-5)

We move all terms to the left:

-2x(20-8x)-(15-5x)-((4x-5))=0

We add all the numbers together, and all the variables

-2x(-8x+20)-(-5x+15)-((4x-5))=0

We multiply parentheses

16x^2-40x-(-5x+15)-((4x-5))=0

We get rid of parentheses

16x^2-40x+5x-((4x-5))-15=0


We calculate terms in parentheses: -((4x-5)), so:

(4x-5)

We get rid of parentheses

4x-5

Back to the equation:

-(4x-5)


We add all the numbers together, and all the variables

16x^2-35x-(4x-5)-15=0

We get rid of parentheses

16x^2-35x-4x+5-15=0

We add all the numbers together, and all the variables

16x^2-39x-10=0

a = 16; b = -39; c = -10;
Δ = b2-4ac
Δ = -392-4·16·(-10)
Δ = 2161
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{-(-39)-\sqrt{2161}}{2*16}=\frac{39-\sqrt{2161}}{32}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-39)+\sqrt{2161}}{2*16}=\frac{39+\sqrt{2161}}{32}
$