15x^2-135x+300=0

Solution for 15x^2-135x+300=0 equation:

15x^2-135x+300=0

a = 15; b = -135; c = +300;
Δ = b2-4ac
Δ = -1352-4·15·300
Δ = 225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{225}=15$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-135)-15}{2*15}=\frac{120}{30}
=4
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-135)+15}{2*15}=\frac{150}{30}
=5
$