Question

resolva as equações em cruz :

x/6=14/21

x/9=18/27

12/x=3/7

15/2=90/x

Answer 1

x/6=14/21 
21x=6*14
21x = 84
x = 84/21
x = 4

x/9=18/27
27x = 9*18
27x = 162
x = 162/27
x = 6

12/x=3/7 
3x=84
x = 84/3
x = 28

15/2=90/x
15x = 2*90
15x = 180
x = 180/15
x = 12