x-30=3x(x+10)

Solution for x-30=3x(x+10) equation:

x-30=3x(x+10)

We move all terms to the left:

x-30-(3x(x+10))=0


We calculate terms in parentheses: -(3x(x+10)), so:

3x(x+10)

We multiply parentheses

3x^2+30x

Back to the equation:

-(3x^2+30x)


We get rid of parentheses

-3x^2+x-30x-30=0

We add all the numbers together, and all the variables

-3x^2-29x-30=0

a = -3; b = -29; c = -30;
Δ = b2-4ac
Δ = -292-4·(-3)·(-30)
Δ = 481
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-29)-\sqrt{481}}{2*-3}=\frac{29-\sqrt{481}}{-6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-29)+\sqrt{481}}{2*-3}=\frac{29+\sqrt{481}}{-6}
$