jika nilai x dan y memenuhi sistem persamaan 2x + y = 5 dan x + 4y = -1 maka nilai x - y =

2x+y = 5 |×1 | 2x+y = 5
x+4y = -1 |×2| 2x+8y = -2
_____________________ -
7y = 7
y = 7/-7
y = -1

Masukan y = -1 ke pers 2x+y = 5
2x+y = 5
2x+(-1) = 5
2x = 5+1
2x = 6
x = 6/2
x = 3

Nilai x-y = 3-(-1) = 4

Semoga membantu

2x + y = 5
x + 4y = -1
x - y = ?

2x + y = 5 .............. (x1)
x + 4y = -1 .............. (x2)

2x + y = 5
2x + 8y = -2
___________ _
-7y = 7
y = -1

2x + y = 5
2x + (-1) = 5
2x = 6
x = 3

x - y = 3 - (-1)
x - y = 4

Semoga membantu :)