X^2-2x-10+2x^2-x=0

Solution for X^2-2x-10+2x^2-x=0 equation:

X^2-2X-10+2X^2-X=0

We add all the numbers together, and all the variables

3X^2-3X-10=0

a = 3; b = -3; c = -10;
Δ = b2-4ac
Δ = -32-4·3·(-10)
Δ = 129
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{-(-3)-\sqrt{129}}{2*3}=\frac{3-\sqrt{129}}{6}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3)+\sqrt{129}}{2*3}=\frac{3+\sqrt{129}}{6}
$