Question

2x-z=10
y+2z=-2
3x-2y=8
please help

Answer 1

2x-z=10
-> Z = ....?

Answer 2

?

Answer 3

2x-10?

Answer 4

Correct, now replace 2x-10 into y+2z=-2

Answer 5

y+4x-20

Answer 6

nm

Answer 7

y + 2z = -2
y + 4x -20 = -2
Can you simplify it?

Answer 8

y+4x=18

Answer 9

3x-2y = 8
4x + y = 18
Can you solve it?

Answer 10

7x-y=26?

Answer 11

No, you need to multiply 2 ( 4x + y = 18 )

Answer 12

\[\begin{bmatrix}
2 & 0 & -1\\
0 & 1 & 2\\
3 & -2 & 0
\end{bmatrix}\begin{bmatrix}
x\\
y\\
z
\end{bmatrix}=\begin{bmatrix}
10\\
-2\\
8
\end{bmatrix}\Longrightarrow\begin{bmatrix}
x\\
y\\
z
\end{bmatrix}=\begin{bmatrix}
4\\
2\\
-2
\end{bmatrix}.\]Use that to check your solution.