Find all values of $x$ such that \frac{2x}{x + 2} = \frac{x}{x - 4}. If you find more than one value, then list your solutions, separated by commas.
2x/(x+2) = x/(x-4)
Get rid of the divisors
2x(x-4) = x(x+2)
Expand
2x^2 - 8x = x^2 +2x
Collecting like terms
x^2 - 10x = 0
Factoring
x(x-10) = 0
x=0, x=10
+1678 
