q^2-13=80

Solution for q^2-13=80 equation:

q^2-13=80

We move all terms to the left:

q^2-13-(80)=0

We add all the numbers together, and all the variables

q^2-93=0

a = 1; b = 0; c = -93;
Δ = b2-4ac
Δ = 02-4·1·(-93)
Δ = 372
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$q_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$q_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{372}=\sqrt{4*93}=\sqrt{4}*\sqrt{93}=2\sqrt{93}$
$q_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-2\sqrt{93}}{2*1}=\frac{0-2\sqrt{93}}{2}
=-\frac{2\sqrt{93}}{2}
=-\sqrt{93}
$
$q_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+2\sqrt{93}}{2*1}=\frac{0+2\sqrt{93}}{2}
=\frac{2\sqrt{93}}{2}
=\sqrt{93}
$