Remember to subtract you change the sign and add. Now the problem is 1/(x-3) + -2/(3-x) = 4 (x^2-9).
Next put the minus sign into the denominator of the second term for 2/-(3-x). Multiply the minus sign through the parenthesis to have -3 + x and rearrange x - 3. Now the problem is 1/(x-3) + 2/(x-3) = 4 (x^2 - 9).
Factor the denominator in the answer to have x^2 - 9 = (X-3) times ( x+ 3).
Multiply both sides of the equation by x-3 to have 1 + 2 = 4/ (x+3)
Multiply both sides by x + 3 to have 3x + 9 = 4
Subtract 9 form both sides to have 3 x = 5
Divide both sides by 3 to have x = 5/3