4/9 = 8x/45 5x/12=2/3 6/7 = 10x/21 8/9 = 4x/27 27/5x = 9/16 решите

1)4/9=8x/45
180=72x
72x=180
x=5/2

2)5x/12=2/3
15x=24
x=8/5

3)6/7=10x/21
126=70x
70x=126
x=9/5

4)8/9=4x/27
216=36x
36x=21x=6

5)27/5x=9/16
27/5x=9/16, x≠0
432=45x
45x=432
x=48/5, x≠0
x=48/5