12x^+21x^2-6x=0

Solution for 12x^+21x^2-6x=0 equation:

12x^+21x^2-6x=0

We add all the numbers together, and all the variables

21x^2+6x=0

a = 21; b = 6; c = 0;
Δ = b2-4ac
Δ = 62-4·21·0
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(6)-6}{2*21}=\frac{-12}{42}
=-2/7
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(6)+6}{2*21}=\frac{0}{42}
=0
$