72^2+65^2=x^2

Solution for 72^2+65^2=x^2 equation:

72^2+65^2=x^2

We move all terms to the left:

72^2+65^2-(x^2)=0

We add all the numbers together, and all the variables

-1x^2+9409=0

a = -1; b = 0; c = +9409;
Δ = b2-4ac
Δ = 02-4·(-1)·9409
Δ = 37636
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{37636}=194$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-194}{2*-1}=\frac{-194}{-2}
=+97
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+194}{2*-1}=\frac{194}{-2}
=-97
$