-2(-x+9)=2(x-9)2x-18=2x-18

Solution for -2(-x+9)=2(x-9)2x-18=2x-18 equation:

-2(-x+9)=2(x-9)2x-18=2x-18

We move all terms to the left:

-2(-x+9)-(2(x-9)2x-18)=0

We add all the numbers together, and all the variables

-2(-1x+9)-(2(x-9)2x-18)=0

We multiply parentheses

2x-(2(x-9)2x-18)-18=0


We calculate terms in parentheses: -(2(x-9)2x-18), so:

2(x-9)2x-18

We multiply parentheses

4x^2-36x-18

Back to the equation:

-(4x^2-36x-18)


We get rid of parentheses

-4x^2+2x+36x+18-18=0

We add all the numbers together, and all the variables

-4x^2+38x=0

a = -4; b = 38; c = 0;
Δ = b2-4ac
Δ = 382-4·(-4)·0
Δ = 1444
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1444}=38$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(38)-38}{2*-4}=\frac{-76}{-8}
=9+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(38)+38}{2*-4}=\frac{0}{-8}
=0
$