9x^2+15x-3=-7

Solution for 9x^2+15x-3=-7 equation:

9x^2+15x-3=-7

We move all terms to the left:

9x^2+15x-3-(-7)=0

We add all the numbers together, and all the variables

9x^2+15x+4=0

a = 9; b = 15; c = +4;
Δ = b2-4ac
Δ = 152-4·9·4
Δ = 81
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{81}=9$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(15)-9}{2*9}=\frac{-24}{18}
=-1+1/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+9}{2*9}=\frac{-6}{18}
=-1/3
$