(2x-2)(x+6)=-5

Solution for (2x-2)(x+6)=-5 equation:

(2x-2)(x+6)=-5

We move all terms to the left:

(2x-2)(x+6)-(-5)=0

We add all the numbers together, and all the variables

(2x-2)(x+6)+5=0

We multiply parentheses ..

(+2x^2+12x-2x-12)+5=0

We get rid of parentheses

2x^2+12x-2x-12+5=0

We add all the numbers together, and all the variables

2x^2+10x-7=0

a = 2; b = 10; c = -7;
Δ = b2-4ac
Δ = 102-4·2·(-7)
Δ = 156
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:

$\sqrt{\Delta}=\sqrt{156}=\sqrt{4*39}=\sqrt{4}*\sqrt{39}=2\sqrt{39}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-2\sqrt{39}}{2*2}=\frac{-10-2\sqrt{39}}{4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+2\sqrt{39}}{2*2}=\frac{-10+2\sqrt{39}}{4}
$