So \(\displaystyle \frac{x}{x+ 10}= \frac{8}{2x- 4}\)?
(For future reference, if you are using standard ASCII characters, write it using parentheses: x/(x+ 10)= 8/(2x- 4). Web readers do not keep spaces so such attempts to "draw" fractions just don't work.)
The first thing you should do is multiply both sides by (x+ 10)(2x- 4) to get rid of the denominators:
\(\displaystyle (x+10)(2x- 4)\frac{x}{x+ 10}= (x+ 10)(2x- 4)\frac{8}{2x- 4}\)
\(\displaystyle (2x- 4)(x)= (x+ 10)(8)\)
\(\displaystyle 2x^2- 4x= 8x+ 80\)
\(\displaystyle 2x^2- 12x- 80= 0\)
\(\displaystyle x^2- 6x- 40= 0\).
Can you solve that quadratic equation? What ever solutions you get, be sure to check them back into the original equation. Multiplying both sides of an equation by functions of the unknown (here x+ 10 and 2x- 4) can introduce "extraneous solutions" that satisfy the new equation but not the original.)