Пошаговое объяснение:
1.
15(у+2)=2(у+5)
15y + 30 = 2y + 10
15y - 2y = 10 - 30
13y = -20
y = -20:13
y = -1 7/13
2.
1,5у-0,5у=8(у-1)
y = 8y - 8
8y - y = 8
7y = 8
y = 8:7
y = 1 1/7
3.
7х-3(х+1)=18
7x - 3x - 3 = 18
4x - 3 = 18
4x = 18+3
4x = 21
x = 21:4
x = 5,25
Пошаговое объяснение:
1.
15(у+2)=2(у+5)
15y + 30 = 2y + 10
15y - 2y = 10 - 30
13y = -20
y = -20:13
y = -1 7/13
2.
1,5у-0,5у=8(у-1)
y = 8y - 8
8y - y = 8
7y = 8
y = 8:7
y = 1 1/7
3.
7х-3(х+1)=18
7x - 3x - 3 = 18
4x - 3 = 18
4x = 18+3
4x = 21
x = 21:4
x = 5,25