350=-16x^2+156x+15

Solution for 350=-16x^2+156x+15 equation:

350=-16x^2+156x+15

We move all terms to the left:

350-(-16x^2+156x+15)=0

We get rid of parentheses

16x^2-156x-15+350=0

We add all the numbers together, and all the variables

16x^2-156x+335=0

a = 16; b = -156; c = +335;
Δ = b2-4ac
Δ = -1562-4·16·335
Δ = 2896
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:

$\sqrt{\Delta}=\sqrt{2896}=\sqrt{16*181}=\sqrt{16}*\sqrt{181}=4\sqrt{181}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-156)-4\sqrt{181}}{2*16}=\frac{156-4\sqrt{181}}{32}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-156)+4\sqrt{181}}{2*16}=\frac{156+4\sqrt{181}}{32}
$