25x^2+8=90x

Solution for 25x^2+8=90x equation:

25x^2+8=90x

We move all terms to the left:

25x^2+8-(90x)=0

a = 25; b = -90; c = +8;
Δ = b2-4ac
Δ = -902-4·25·8
Δ = 7300
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:

$\sqrt{\Delta}=\sqrt{7300}=\sqrt{100*73}=\sqrt{100}*\sqrt{73}=10\sqrt{73}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-90)-10\sqrt{73}}{2*25}=\frac{90-10\sqrt{73}}{50}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-90)+10\sqrt{73}}{2*25}=\frac{90+10\sqrt{73}}{50}
$