Selesaikan sistem persamaan di bawah ini dengan metode eliminasi.

4.
a). HP = {6 , 5}
x + y = 11
x – y = 1
_______ –
2y = 10
y = 5

x + y = 11
x – y = 1
_______ +
2x = 12
x = 6

b). HP = {2,6}
3r – s = 0
2r + s = 10
________ +
5r = 10
r = 2

3r – s = 0 (×2)
2r + s = 10 (×3)
_________
6r – 2s = 0
6r + 3s = 30
_________ –
-5s = -30
s = 6

c). HP = {2,1}
9n + m = 19
6n – m = 11
_________ +
15n = 30
n = 2

9n + m = 19 (×2)
6n – m = 11 (×3)
________
18n + 2m = 38
18n – 3m = 33
___________ –
5m = 5
m = 1

d). HP = {12/5 , -6/25}
3r + 5s = 6
2r – 5s = 6
________ +
5r = 12
r = 12/5

3r + 5s = 6 (×2)
2r – 5s = 6 (×3)
_________
6r + 10s = 12
6r – 15s = 18
__________ –
25s = -6
s = -6/25

e). HP = {1 , 1}
4p + 3q = 7
6p – 3q = 3
_________ +
10p = 10
p = 1

4p + 3q = 7 (×3)
6p – 3q = 3 (×2)
__________
12p + 9q = 21
12p – 6q = 6
__________ –
15 q = 15
q = 1

f). HP = {3 , -3}
3x + 2y = 3
x – y = 6 (×2)
________
3x + 2y = 3
2x – 2y = 12
_________ +
5x = 15
x = 3

3x + 2y = 3
x – y = 6 (×3)
_________
3x + 2y = 3
3x – 3y = 18
_________ –
5y = -15
y = -3