hasil dari a-2b=2 dan 3b-5a=4

Dik : a-2b = 2
        -5a + 3b = 4
Dit : a = ?                        b = ?
Jawab :
a-2b = 2              |x 5|   5a - 10b = 10
-5a + 3b = 4        |x 1|   -5a + 3b = 4   +
                                    -7b = 14
                                       b = -2
Subtitusikan b = -2 ke persamaan a - 2b = 2
a - 2 . (-2) = 2
a +4 = 2
a = -2


Maaf klo salah

a - 2b = 2
a = 2 + 2b

3b - 5a
4 = 3b - 5(2+2b)
4 = 3b - 10 - 10b
4 + 10 = -7b
14 = -7b
14/-7 = b
b = -2

kalau b = -2 maka,
a - 2(-2) = 2
a + 4 = 2
a = 2 - 4
a = -2

a = -2
b = -2