8b^2-10b-2=-4

Solution for 8b^2-10b-2=-4 equation:

8b^2-10b-2=-4

We move all terms to the left:

8b^2-10b-2-(-4)=0

We add all the numbers together, and all the variables

8b^2-10b+2=0

a = 8; b = -10; c = +2;
Δ = b2-4ac
Δ = -102-4·8·2
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-10)-6}{2*8}=\frac{4}{16}
=1/4
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-10)+6}{2*8}=\frac{16}{16}
=1
$