Question

Здраствуйте помогите пожалуйста

Answer 1

1) 2/3:(4/9х-4/9)+1/20=4,/5
2/3:(4/9х-4/9)=4/5-1/20
4/9х-4/9=2/3:(16/20-1/20)
4/9х=2/3:15/20+4/9
4/9х=2/3*4/3+4/9
4/9х=8/9+4/9
4/9х=12/9
х=12/9:4/9
х=12/9*9/4
х=3
2) 5/7:(6/7х+3/7)-1/2=1/6
5/7:(6/7х+3/7)=1/6+1/2
5/7:(6/7х+3/7)=1/6+3/6
6/7х+3/7=5/7:4/6
6/7х=5*6/7*4-3/7
6/7х=30/28-3/7
6/7х=30/28-12/28
6/7х=18/28
х=18/28:6/7
х=18*7/28*6
х=3/4