2b^2=-18b-40

Solution for 2b^2=-18b-40 equation:

2b^2=-18b-40

We move all terms to the left:

2b^2-(-18b-40)=0

We get rid of parentheses

2b^2+18b+40=0

a = 2; b = 18; c = +40;
Δ = b2-4ac
Δ = 182-4·2·40
Δ = 4
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4}=2$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(18)-2}{2*2}=\frac{-20}{4}
=-5
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(18)+2}{2*2}=\frac{-16}{4}
=-4
$