Question

Ada yang tau nomer 19? Tolong bantuannya ya kawan ...

Answer 1

2x - 3y = -1 |x1|
x - 4y = 2    |x2|
Sistem eliminasi:
2x - 3y = -1
2x - 8y = 4
~ Kurangi ~
(-3-(-8))y = -1-4
       5y = -5
         y = -1

Sehingga,
Substitusikan,
x - 4y = 2
x - 4(-1) = 2
x + 4 = 2
x = 2 - 4
x = -2

Maka,
x - y = -2 - (-1)
x - y = -2 + 1
x - y = -1 [A]