(-6x-9)(-6x+4)=(-6x-9)

Solution for (-6x-9)(-6x+4)=(-6x-9) equation:

(-6x-9)(-6x+4)=(-6x-9)

We move all terms to the left:

(-6x-9)(-6x+4)-((-6x-9))=0

We multiply parentheses ..

(+36x^2-24x+54x-36)-((-6x-9))=0


We calculate terms in parentheses: -((-6x-9)), so:

(-6x-9)

We get rid of parentheses

-6x-9

Back to the equation:

-(-6x-9)


We get rid of parentheses

36x^2-24x+54x+6x-36+9=0

We add all the numbers together, and all the variables

36x^2+36x-27=0

a = 36; b = 36; c = -27;
Δ = b2-4ac
Δ = 362-4·36·(-27)
Δ = 5184
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{5184}=72$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(36)-72}{2*36}=\frac{-108}{72}
=-1+1/2
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(36)+72}{2*36}=\frac{36}{72}
=1/2
$