x=3x^2-15x

Solution for x=3x^2-15x equation:

x=3x^2-15x

We move all terms to the left:

x-(3x^2-15x)=0

We get rid of parentheses

-3x^2+x+15x=0

We add all the numbers together, and all the variables

-3x^2+16x=0

a = -3; b = 16; c = 0;
Δ = b2-4ac
Δ = 162-4·(-3)·0
Δ = 256
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{256}=16$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(16)-16}{2*-3}=\frac{-32}{-6}
=5+1/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(16)+16}{2*-3}=\frac{0}{-6}
=0
$