15 x 2 mũ 2 3 18 July 8, 2019 16 32 64 128 15+(x+2)mũ 2 3=18 15 mở ngoặc x 2 mũ 2 chia 3 18 15 1/2 x 18 15 × 15 × 2 15 x 2 1/2 2 15 x 3 15 x 10
