9x^2-52x+72=0

Solution for 9x^2-52x+72=0 equation:

9x^2-52x+72=0

a = 9; b = -52; c = +72;
Δ = b2-4ac
Δ = -522-4·9·72
Δ = 112
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{112}=\sqrt{16*7}=\sqrt{16}*\sqrt{7}=4\sqrt{7}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-52)-4\sqrt{7}}{2*9}=\frac{52-4\sqrt{7}}{18}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-52)+4\sqrt{7}}{2*9}=\frac{52+4\sqrt{7}}{18}
$