Question

Diketahui sistem persamaan linear 3x + y = -10 dan 2x + 3y= -16. nilai 3x - 2y adalah..

Mohon bantuannya. terimakasih :)

Answer 1

3x + y = -10 ×2 6× + 2y = -20
2× + 3y = -16 ×3 6x + 9y = -48
(dikurangi)
-7y = 28 》 y = -4
3x + y = -10
3x + (-4) = -10
3× = -6 》× = -2

3× - 2y = 3(-2) - 2(-4)
= -6 + 8 = 2

Answer 2

3x + y = -10  x 2<<<<--- Eliminasi
2x + 3y = -16    x 3
6x + 2y = -20 ... pers 1
6x + 9y= -48 .... pers 2
______________-
-7y = 28
y = 28/7
y = 4 ... pers 3

Sibtitusikan ke pers 2
2x + 3y = -16
2x + 3.4 = -16
2x + 12 = -16
2x = -16 - 12
2x = -28
x = 28/2
x= 14

3x - 2y
3.14 - 2.4
42 - 8 = 34

Maaf kalo salah ..