step 1: set your equations equal to DEF which is 76 (2x + 12 + 5x - 6 = 76)
step 2: find the x value by simplifying (x = 10)
step 3: find DEG by plugging in x (2(10) + 12 = 32)
step 4: find GEF by plugging in x (5(10) - 6 = 44)
Answer: mDEG = 32 and mGEF = 44