5x+27=4x+21
5x - 4x = 21 - 27
x = -6
ответ: -6.
4(3-2y)-42=2(3+2y)
12 - 8y - 42 = 6 + 4y
-8y - 4y = 6 + 42 - 12
- 12y = 36
y = -3
ответ: - 3.
5x+27=4x+21
x+27-21=0
x+6=0
x=-6
4(3-2y)-42=2(3+2y)
12-8y-42-2*(3+2y)=0
-30-8y-2*(3+2y)=0
-30-8y-(6+4y)=0
-30-8y-6-4y=0
-36-8y-4y=0
-36-12y=0
y=-36/12
y=-3
