Answer:
Case 1 : x = - 2, y = 3
Case 2 : x = 5. y = 2
Explanation:
Case 1
5y + x = 13 --------> Eq 1
y - x = 5 ---------> Eq 2
Add both Eq 1 and y,
5y + x = 13
y - x = 5
________
6y + 0 = 18
6y = 18
y = 18/6
y = 3
Substitute y = 3 in Eq 2,
3 - x = 5
3 - 5 = x
- 2 = x
x = - 2
Hence,
x = - 2
y = 3
Case 2
2x + y = 12 ---------> Eq 1
6x + 5y = 40 -----------> Eq 2
Multiply Eq 1 with 3,
3(2x + y = 12)
6x + 3y = 36 --------> Eq 3
Eq 2 - Eq 3,
6x + 5y = 40
- 6x - 3y = - 36
_____________
0 + 2y = 4
2y = 4
y = 4/2
y = 2
Substitute y = 2 in equation 1,
2x + 2 = 12
2x = 12 - 2
2x = 10
x = 10/2
x = 5
Hence,
x = 5
y = 2