Выразить у через x: 3x + y = 4 5x – y = 2 1/2y – x = 7 2x + 1/3y – 1 = 0

Question

Выразить у через x:
3x + y = 4
5x – y = 2
1/2y – x = 7
2x + 1/3y – 1 = 0

Answer 1

3x + y = 4
y=4-3x

5x – y = 2
y=5x-2
 
1/2y – x = 7
1/2y=7+x
y=2(7+x)
 
2x + 1/3y – 1 = 0
1/3y=1-2x
y=3(1-2x)