Question

If $\left| \begin{matrix} 1 & 1 & 0 \\\ 2 & 0 & 3 \\\ 5 & -6 & x \\\ \end{matrix} \right|=29,$ then $x$ is

• A. $1$
• B. $2$
• C. $3$
• D. $4$

Answer 1

Answer: (B)

$2$

Answer 2

Given, that, $\left| \begin{matrix} 1 & 1 & 0 \\\ 2 & 0 & 3 \\\ 5 & -6 & x \\\ \end{matrix} \right|=29$
$\Rightarrow$ $1(0+18)-1(2x-15)=29$
$\Rightarrow$ $18-2x+15=29$
$\Rightarrow$ $2x=4$
$\Rightarrow$ $x=2$