6x(x+3)-9=16x-8

Solution for 6x(x+3)-9=16x-8 equation:

6x(x+3)-9=16x-8

We move all terms to the left:

6x(x+3)-9-(16x-8)=0

We multiply parentheses

6x^2+18x-(16x-8)-9=0

We get rid of parentheses

6x^2+18x-16x+8-9=0

We add all the numbers together, and all the variables

6x^2+2x-1=0

a = 6; b = 2; c = -1;
Δ = b2-4ac
Δ = 22-4·6·(-1)
Δ = 28
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:

$\sqrt{\Delta}=\sqrt{28}=\sqrt{4*7}=\sqrt{4}*\sqrt{7}=2\sqrt{7}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(2)-2\sqrt{7}}{2*6}=\frac{-2-2\sqrt{7}}{12}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(2)+2\sqrt{7}}{2*6}=\frac{-2+2\sqrt{7}}{12}
$