-7y+5+4.5-1= -7y+8.5= -7*(4/5)+17/2= -28/5+17/2= -56/10+85/10= 29/10= 2.9
8b+55=167
8b=167-55
8b=112
b=112:8
b=14
Ответ:b=14
7y+9-5y=13
7y-5y=13-9
2y=4
y=0,5
Ответ:y=0,5
(720+e)*501=365730
720+e=365730:501
720+e=730
e=730-720
e=10
Ответ:e=10
(k+2958):87=134
k+2958=134*87
k+2958=11658
k=11658-2958
k=8700
Ответ:k=8700
Р = 7 + 2 + 6 = 15 ( дм )
7/1-5/12=(84-5)/12=81/12 4/1-32/9=(36/32)/9=4/9 49/8-19/8=30/8=3 3/4