Penjelasan dengan langkah-langkah:

A.

4x + y = 9 ...........(1)

x + 2y = 10

x = 10 - 2y...........(2)

subtitusikan x ke (1)

4(10 - 2y) + y = 9

40 - 8y + y = 9

40 - 7y = 9

7y = 40 - 9

7y = 31

y = 31/7

x = 10 - 2y

x = 10 - 2(31/7)

x = 10 - 62/7 = 70/7 - 62/7

x = 8/7

HP = {8/7, 31/7}

B.

2x + y = 5 ...............(1)

x - y =* 1

x = y + 1 ...................(2)

subtitusikan x ke (1)

2(y + 1) + y = 5

2y + 2 + y = 5

3y = 5 - 2

3y = 3

y = 1

x - y = 1

x - 1 = 1

x = 1 + 1

x = 2

HP = {2, 1}

C.

x + y = 5 ..........(1)

y = x + 1............(2)

subtitusikan y ke (1)

x + (x + 1) = 5

2x + 1 = 5

2x = 5 - 1

2x = 4

x = 2

y = x + 1

y = 2 + 1

y = 3

HP = {2, 3}