Everything must add up to 180 so you would add the 2 you already have
65 + 79 = 144 then add add each one of the answer choices to 144 to see what comes out as 180
144 + 56 = 200 (not the answer)
144 + 36 = 180 (Correct answer
144 + 14 = 158 (not the answer)
144 + 144 = 288 (not the answer)
so the correct answer is 36