(6x+6)(5x+8)=0

Solution for (6x+6)(5x+8)=0 equation:

(6x+6)(5x+8)=0

We multiply parentheses ..

(+30x^2+48x+30x+48)=0

We get rid of parentheses

30x^2+48x+30x+48=0

We add all the numbers together, and all the variables

30x^2+78x+48=0

a = 30; b = 78; c = +48;
Δ = b2-4ac
Δ = 782-4·30·48
Δ = 324
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{324}=18$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(78)-18}{2*30}=\frac{-96}{60}
=-1+3/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(78)+18}{2*30}=\frac{-60}{60}
=-1
$