Question

Himpunan penyelasaian dari 2x + y+z= 9; x+ 2y -z =6 dan 3x-y+z =8

Answer 1

2x + y + z = 9
x + 2y - z = 6
--------------------- (+)
3x + 3y = 15 (I)

2x + y + z = 9
3x - y + z = 8
--------------------- (-)
-x + 2y = 1 (II)

I & II
3x + 3y = 15 |x1
-x + 2y = 1 |x3

3x + 3y = 15
-3x + 6y = 3
------------------- (+)
9y = 18, y = 2

I => 3x + 3(2) = 15
3x = 15 - 6 = 9
x = 2

2(2) + 2 + z = 9
4 + 2 + z = 9
6 +z = 9
z = 9 - 6 = 3

Hp = {(2, 2, 3)}