Discussion Forum

If $\begin{bmatrix}1 & x & 1 \ \end{bmatrix}$ $\begin{bmatrix}1 & 3 & 2\\0 & 5 & 1 \\0 &3 & 2\end{bmatrix}\begin{bmatrix}x \\1 \\ -2 \end{bmatrix}$ = 0 then x is

Answer:

Explanation:

We have 

$\begin{bmatrix}1 & x & 1 \ \end{bmatrix}$ $\begin{bmatrix}1 & 3 & 2\\0 & 5 & 1 \\0 &3 & 2\end{bmatrix}\begin{bmatrix}x \\1 \\ -2 \end{bmatrix}$ = 0

$\Rightarrow\begin{bmatrix}1 & 5x+6 & x+4\\\end{bmatrix}\begin{bmatrix}x \\1 \\ -2 \end{bmatrix}$=0

x + 5x + 6 - 2x - 8 = 0

→ 4x - 2 =0

→ x = 1/2