6x(5x-2)+12=30

Solution for 6x(5x-2)+12=30 equation:

6x(5x-2)+12=30

We move all terms to the left:

6x(5x-2)+12-(30)=0

We add all the numbers together, and all the variables

6x(5x-2)-18=0

We multiply parentheses

30x^2-12x-18=0

a = 30; b = -12; c = -18;
Δ = b2-4ac
Δ = -122-4·30·(-18)
Δ = 2304
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{2304}=48$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-12)-48}{2*30}=\frac{-36}{60}
=-3/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-12)+48}{2*30}=\frac{60}{60}
=1
$