giai gium bai toan tim X X x 9: 9=44:4, X:2:2+18=25

Chào con! X × 9 : 9 = 44 : 4 X × 9 : 9 = 11 X × 9 = 11 × 9 X = 11 X : 2 : 2 + 18 = 25 X : 2 : 2 = 25 - 18 X : 2 : 2 = 7 X : 2 = 7 × 2 X : 2 = 14 X = 14 × 2 X = 28