#4
Expression: 4x - 8
Ana age = 4×5 - 8 = 12
#5
Expression: 30 + 2x
Total amount = 30 + 2×8 = 46
#6
52 - 3y = 30
If y = 2, then 52 - 3×2 = 46
#7
Expression: (3/4)x - 10
Weight of blue suitcase = 3/4 × 36 - 10 = 17
Weight of both suitcases = 17 + 36 = 53
