tolong dijawab no 33-35 pake jalan cara

33. 5x - 4y = -1 → ×2
10x + 2y = 3 → ×1
__________
10x - 8y = -2
10x + 2y = 3
__________ -
-10y = -5
y = -5 / -10
y = ½
5x - 4y = -1
5x - (4×½) = -1
5x - 2 = -1
5x= -1 + 2
5x = 1
x = 1/5 → (D) ←

34. 3x + y = -2 → ×3
-2x + 3y = 5 → ×1
__________
9x + 3y = -6
-2x + 3y = 5
__________ -
11x = -11
x = -11 / 11
x = -1
3x + y = -2
(3×-1) + y = -2
-3 + y = -2
y = -2 + 3
y = 1
Maka, x - y = (-1) - 1 = -2 (A)

35. 3x + y = -7 → ×2
2x - 3y = 10 → ×3
_________
6x + 2y = -14
6x - 9y = 30
_________ -
11y = -44
y = -44 / 11
y = -4
3x + y = -7
3x + (-4) = -7
3x = -7 + 4
3x = -3
x = -3 / 3
x = -1
Maka, himpunannya = D. {(-1, -4)}