5b2-7=92

Solution for 5b2-7=92 equation:

5b^2-7=92

We move all terms to the left:

5b^2-7-(92)=0

We add all the numbers together, and all the variables

5b^2-99=0

a = 5; b = 0; c = -99;
Δ = b2-4ac
Δ = 02-4·5·(-99)
Δ = 1980
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:

$\sqrt{\Delta}=\sqrt{1980}=\sqrt{36*55}=\sqrt{36}*\sqrt{55}=6\sqrt{55}$
$b_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-6\sqrt{55}}{2*5}=\frac{0-6\sqrt{55}}{10}
=-\frac{6\sqrt{55}}{10}
=-\frac{3\sqrt{55}}{5}
$
$b_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+6\sqrt{55}}{2*5}=\frac{0+6\sqrt{55}}{10}
=\frac{6\sqrt{55}}{10}
=\frac{3\sqrt{55}}{5}
$