2x^2-5x^2-7x=0

Solution for 2x^2-5x^2-7x=0 equation:

2x^2-5x^2-7x=0

We add all the numbers together, and all the variables

-3x^2-7x=0

a = -3; b = -7; c = 0;
Δ = b2-4ac
Δ = -72-4·(-3)·0
Δ = 49
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{49}=7$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-7)-7}{2*-3}=\frac{0}{-6}
=0
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-7)+7}{2*-3}=\frac{14}{-6}
=-2+1/3
$