7b^2+4=672

Solution for 7b^2+4=672 equation:

7b^2+4=672

We move all terms to the left:

7b^2+4-(672)=0

We add all the numbers together, and all the variables

7b^2-668=0

a = 7; b = 0; c = -668;
Δ = b2-4ac
Δ = 02-4·7·(-668)
Δ = 18704
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:

$\sqrt{\Delta}=\sqrt{18704}=\sqrt{16*1169}=\sqrt{16}*\sqrt{1169}=4\sqrt{1169}$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-4\sqrt{1169}}{2*7}=\frac{0-4\sqrt{1169}}{14}
=-\frac{4\sqrt{1169}}{14}
=-\frac{2\sqrt{1169}}{7}
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+4\sqrt{1169}}{2*7}=\frac{0+4\sqrt{1169}}{14}
=\frac{4\sqrt{1169}}{14}
=\frac{2\sqrt{1169}}{7}
$