3x2+9x=65

Solution for 3x2+9x=65 equation:

3x^2+9x=65

We move all terms to the left:

3x^2+9x-(65)=0

a = 3; b = 9; c = -65;
Δ = b2-4ac
Δ = 92-4·3·(-65)
Δ = 861
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{861}}{2*3}=\frac{-9-\sqrt{861}}{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(9)+\sqrt{861}}{2*3}=\frac{-9+\sqrt{861}}{6}
$