(4g+7)(g+8)=0

Solution for (4g+7)(g+8)=0 equation:

(4g+7)(g+8)=0

We multiply parentheses ..

(+4g^2+32g+7g+56)=0

We get rid of parentheses

4g^2+32g+7g+56=0

We add all the numbers together, and all the variables

4g^2+39g+56=0

a = 4; b = 39; c = +56;
Δ = b2-4ac
Δ = 392-4·4·56
Δ = 625
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$g_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$g_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{625}=25$
$g_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(39)-25}{2*4}=\frac{-64}{8}
=-8
$
$g_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(39)+25}{2*4}=\frac{-14}{8}
=-1+3/4
$