(2g-15)g=9

Solution for (2g-15)g=9 equation:

(2g-15)g=9

We move all terms to the left:

(2g-15)g-(9)=0

We multiply parentheses

2g^2-15g-9=0

a = 2; b = -15; c = -9;
Δ = b2-4ac
Δ = -152-4·2·(-9)
Δ = 297
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$g_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$g_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{297}=\sqrt{9*33}=\sqrt{9}*\sqrt{33}=3\sqrt{33}$
$g_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-15)-3\sqrt{33}}{2*2}=\frac{15-3\sqrt{33}}{4}
$
$g_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-15)+3\sqrt{33}}{2*2}=\frac{15+3\sqrt{33}}{4}
$