Those are called binomials & you have to use the distributive property. first: 3(x+1) distributed & simplified 3x+3 & 5(x-2) distributed & simplified is 5x-10, therefore 3(x+1) = 3x+3 & 5(x-2) = 5x-10. always simplify before solving any algebraic problem! second: so now we can say... 3x + 3 = 5x - 10 + 7 . third: now we combine like terms by adding the -10 & 7 (on the right side) together to get -3. fourth: now we have to isolate the variables by doing the opposite function on each side! it should look like this right now: 3x + 3 = 5x - 3 ... subtract the 3x, on both sides, from the 5x to get 2x. looks like this now: 3 = 2x - 3 now add the -3 (on the right) on the both sides looks like this now: 6 = 2x fifth: now divide to get 3. X = 3 !!!!!