2x^2-9x-16=-9

Solution for 2x^2-9x-16=-9 equation:

2x^2-9x-16=-9

We move all terms to the left:

2x^2-9x-16-(-9)=0

We add all the numbers together, and all the variables

2x^2-9x-7=0

a = 2; b = -9; c = -7;
Δ = b2-4ac
Δ = -92-4·2·(-7)
Δ = 137
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-9)-\sqrt{137}}{2*2}=\frac{9-\sqrt{137}}{4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-9)+\sqrt{137}}{2*2}=\frac{9+\sqrt{137}}{4}
$