270=3x^2+8x

Solution for 270=3x^2+8x equation:

270=3x^2+8x

We move all terms to the left:

270-(3x^2+8x)=0

We get rid of parentheses

-3x^2-8x+270=0

a = -3; b = -8; c = +270;
Δ = b2-4ac
Δ = -82-4·(-3)·270
Δ = 3304
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:

$\sqrt{\Delta}=\sqrt{3304}=\sqrt{4*826}=\sqrt{4}*\sqrt{826}=2\sqrt{826}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-8)-2\sqrt{826}}{2*-3}=\frac{8-2\sqrt{826}}{-6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-8)+2\sqrt{826}}{2*-3}=\frac{8+2\sqrt{826}}{-6}
$