7x(-2x)=5x

Solution for 7x(-2x)=5x equation:

7x(-2x)=5x

We move all terms to the left:

7x(-2x)-(5x)=0

We add all the numbers together, and all the variables

-5x+7x(-2x)=0

We multiply parentheses

-14x^2-5x=0

a = -14; b = -5; c = 0;
Δ = b2-4ac
Δ = -52-4·(-14)·0
Δ = 25
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{25}=5$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-5)-5}{2*-14}=\frac{0}{-28}
=0
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-5)+5}{2*-14}=\frac{10}{-28}
=-5/14
$