3b^2-30=18b

Solution for 3b^2-30=18b equation:

3b^2-30=18b

We move all terms to the left:

3b^2-30-(18b)=0

a = 3; b = -18; c = -30;
Δ = b2-4ac
Δ = -182-4·3·(-30)
Δ = 684
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{684}=\sqrt{36*19}=\sqrt{36}*\sqrt{19}=6\sqrt{19}$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-18)-6\sqrt{19}}{2*3}=\frac{18-6\sqrt{19}}{6}
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-18)+6\sqrt{19}}{2*3}=\frac{18+6\sqrt{19}}{6}
$