Lily1901

A) 2x + 2y = 22 | 2x - 2y = 6

2x = 22 - 2y

22 - 2y - 2y = 6

- 4y = 6 - 22 = -16

40y = 16

y = 16/4

y = 4 | x = 7

B) 2x - 2y = 12 | 2x + 2y = -14

2x = 12 + 2y

12 + 2y + 2y = -14

4y = -14 - 12 = -26

y = -26/4

y = -6,5 | x = -0,5

C) x - y = 6 | x + y = -7

x = 6 + y

6 + y + y = -7

2y = -13

y = -13/2

y = -6,5 | x = -0,5

D) x= 5 - 3y | 2x - y = -4

2(5 - 3y) - y = -4

10 - 6y - y = -4

-7y = -14

y = 2 | x = -1