x-y+7z=12
4x+4y+7z=6 tolong di Jawab contoh di gambar
Ambil persamaan (1) dan (2)
Eliminasi y
3x + 4y + 5z = 3 | ×1 | 3x + 4y + 5z = 3
x - y + 7z = 12 | ×4 | 4x - 4y + 28z = 48
----------------------------------------------------------- +
7x + 33z = 51......(4)
Ambil persamaan (1) dan (3)
3x + 4y + 5z = 3
4x + 4y + 7z = 6
------------------------- -
-x - 2z = -3.......(5)
Didapat persamaan (4) dan (5)
7x + 33z = 51
-x - 2z = -3
Eliminasi x
7x + 33z = 51 | ×1 | 7x + 33z = 51
-x - 2z = -3 | ×7 | -7x - 14z = -21
------------------------------------------------- +
19z = 30
z = 30/19
Substitusi z = 30/19 pada persamaan (5)
-x - 2z = -3
-x - 2( 30/19 ) = -3
-x - 60/19 = -3
-60/19 + 3 = x
-60/19 + 57/19 = x
x = -3/19
Substitusi x = -3/19 dan z = 30/19 pada persamaan (2)
x - y + 7z = 12
-3/19 - y + 7( 30/19 ) = 12
-3/19 + y + 210/19 = 12
207/19 + y = 12
y = 12 - 207/19
y = 228/19 - 207/19
y = 21/19
HP = { ( -3/19, 21/19, 30/19 ) }
