3x(x+22)=90

Solution for 3x(x+22)=90 equation:

3x(x+22)=90

We move all terms to the left:

3x(x+22)-(90)=0

We multiply parentheses

3x^2+66x-90=0

a = 3; b = 66; c = -90;
Δ = b2-4ac
Δ = 662-4·3·(-90)
Δ = 5436
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:

$\sqrt{\Delta}=\sqrt{5436}=\sqrt{36*151}=\sqrt{36}*\sqrt{151}=6\sqrt{151}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(66)-6\sqrt{151}}{2*3}=\frac{-66-6\sqrt{151}}{6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(66)+6\sqrt{151}}{2*3}=\frac{-66+6\sqrt{151}}{6}
$