I believe this is algebra and if I correctly remember you have to look at the related numbers and take the symbol to the number on the left and make a problem out of it, if you understand what I mean. so 5x + 2x = 7x and 6 - 3 = 3.
7x = 2(3)
I hope you understand what I said and if you do it should help you in future questions. The bold numbers are the answer.