Question

Cara Pengerjaannya Gmn Ya?

Answer 1

Verified answer

-3x + 2y = 8        ..............................(1)
2x - y = -10           ............................(2)

dari (1) dan (2)
-3x + 2y = 8     |×1|      -3x + 2y = 8
2x - y = -10      |×2|       4x - 2y = -20
                                ----------------------- (+)
                                         x = -12
subtitusikan x = -12 ke pers. (1)
-3x + 2y = 8
-3(-12) + 2y = 8
36 + 2y = 8
2y = 8 - 36
2y = -28
y = -14

jadi a = -12
       b = -14

a - 2b
= -12 - 2(-14)
= -12 + 28
= 16

Answer 2

-3a + 2b = 8 | 2 | -6a + 4b = 16
2a - b = -10 | 3 | 6a - 3b = -30
---------------------- +
b = -14

-3a + 2b = 8
-3a + 2 X (-14) = 8
-3a + (-28) = 8
-3a = 36
a = 12

a -2b = 12 - 2 X (-14)
= 12 + 28
= 40