algebra

step 1: expand

$2x(x-1)=2x^2-2x$

$2x^2-2x=-50$

We hen add 50 to both sides to get the quadratic

$2x^2-2x+50=0$

Applying Vietas, we have the sum of the roots is $-b/a$ and the product is $c/a$ where $ax^2+bx+c=0$

so we have $2/2=\boxed{1}$