9x^2-125/5=4x

Solution for 9x^2-125/5=4x equation:

9x^2-125/5=4x

We move all terms to the left:

9x^2-125/5-(4x)=0

We add all the numbers together, and all the variables

9x^2-4x-25=0

a = 9; b = -4; c = -25;
Δ = b2-4ac
Δ = -42-4·9·(-25)
Δ = 916
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:

$\sqrt{\Delta}=\sqrt{916}=\sqrt{4*229}=\sqrt{4}*\sqrt{229}=2\sqrt{229}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-4)-2\sqrt{229}}{2*9}=\frac{4-2\sqrt{229}}{18}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+2\sqrt{229}}{2*9}=\frac{4+2\sqrt{229}}{18}
$