8b+4=4b2

Solution for 8b+4=4b2 equation:

8b+4=4b^2

We move all terms to the left:

8b+4-(4b^2)=0

determiningTheFunctionDomain
-4b^2+8b+4=0

a = -4; b = 8; c = +4;
Δ = b2-4ac
Δ = 82-4·(-4)·4
Δ = 128
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:

$\sqrt{\Delta}=\sqrt{128}=\sqrt{64*2}=\sqrt{64}*\sqrt{2}=8\sqrt{2}$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(8)-8\sqrt{2}}{2*-4}=\frac{-8-8\sqrt{2}}{-8}
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(8)+8\sqrt{2}}{2*-4}=\frac{-8+8\sqrt{2}}{-8}
$