mohon bantuannya, insyaallah dapet pahala materinya matriks

Dari matriks tsb. didapat:

3a + 2b = 1 (i)

0.a + (-1)b = -1
-b = -1
b = 1

(-2)a + 5b = c
-2a + 5b = c (ii)

Masukkan nilai b ke persamaan (i)
3a + 2b = 1
3a + 2(1) = 1
3a + 2 = 1
3a = -1
a = -1/3

Masukkan nilai a dan b ke persamaan (iii)
-2a + 5b = c
-2(-1/3) + 5(1) = c
c = 2/3+ 5
c = 2/3 + 15/3
c = 17/3


a + ab + abc
= -1/3 + (-1/3)(1) + (-1/3)(1)(17/3)
= -1/3 - 1/3 - 17/9
= -2/3 - 17/9
= -6/9 - 17/9
= -23/9

*tidak ada di pilihan jawaban*