7/4 x 15/7 + 13/7 x 9/4 - 7/4 x2/7
=7/4 x 15/7- 7/4 x2/7+ 13/7 x 9/4
=7/4 x (15/7 - 2/7) + 13/7 x 9/4
=7/4 x 13 /7 + 13/7 x 9/4
=13/7 x (7/4+9/4)
=13/7 x 16/4
=13/7 x 4
=52/7
k mk nha
sorry câu trả lời vừa nãy mk ấn nhầm
7/4 x 15/7 + 13/7 x 9/4 - 7/4 x2/7
=7/4 x 15/7 - 7/4 x 2/7 + 13/7 x 9/4