5 x y = 35
= 35 : 5
= 7
y x 1 =30
= 30 : 1
= 30
y x 5 = 0
= 0 : 5
= 0
y : 3 = 4
= 4 x 3
= 12
y : 1 = 30
= 30 x 1
= 30
4 x y = 0
y = 4 x 0
= 0
5*y=35
= 35 : 5
y = 7
y*1=30
y = 30 : 1
y = 30
y*5=0
y = 0 : 5
y = 0
y:3=4
y = 3 x 4
y = 12
y:1=30
y = 30 x 1
y = 30
4*y=0
y = 4 : 0
y = 0
hok tốt