Jawapan

2015-10-01T12:08:20+08:00
1/2 m + 3n = 8
1/2 m = 8 - 3n
m = 2(8 - 3n)

1) gantikan ke dalam persamaan;
2m - n = -7
2 [2(8 - 3n) - n = -7
2(16 - 6n) - n = -7
32 - 12n - n = -7
32 - 13n = -7
13n = 32 + 7
13n = 39
n = 39/13
n = 3

2) gantikan m = 3 ke dalam persamaan;
m = 2(8 - 3n)
m = 2(8 - 9)
m = 2(-1)
m = -2