Question

Minta tolong dong kak​

Answer 1

Jawaban:

-1

Penjelasan dengan langkah-langkah:

x + 2y + 3z = -6

2x + y - z = 3

-x + y + z = 0 → kali 3 → -3x + 3y + 3z = 0

2x + y - z = 3

-x + y + z = 0

--------------------- +

x + 2y = 3

-3x + 3y + 3z = 0

x + 2y + 3z = -6

----------------------------- -

-4x + y = 6 → dikali 2 → -8x + 2y = 12

-8x + 2y = 12

x + 2x = 3

----------------------- -

-9x = 9

x = 9 : -9

x = -1

Jawabannya C

Kelas 10

Pelajaran Matematika

Bab Persamaan Linear Tiga Variabel

Answer 2

Jawaban:

C. -1

Penjelasan dengan langkah-langkah:

diketahui

x + 2y + 3z = -6 ........(1)

2x + y - z = 3 .............(2)

-x + y + z = 0 .............(3)

ditanya:

nilai x = ...?

Jawab:

(1&2)

x + 2y + 3z = -6 |×1

2x + y -z = 3 |× 2

x+ 2y+3z=-6

4x+2y-2z=6 _

-3x + 5z = -12 .......(4)

(2&3)

2x+y-z=3

-x+y+z=0 _

3x -2z = 3 .......(5)

(4&5)

-3x+5z=-12

3x-2z=3 +

3z = -9

z = -3

# cari nilai x

3x -2z = 3

3x - 2(-3) = 3

3x + 6 = 3

3x = 3 -6

3x = -3

x = -1