Question

If $\left|\begin{array}{cc}x+2& x\\ 4& 3\end{array}\right|=0$ find the value of x.

Answer 1

We have $\left|\begin{array}{cc}x+2& x\\ 4& 3\end{array}\right|=0$

$\Rightarrow 3(x+2)-4x=0$

$\Rightarrow 3x+6-4x=0$

$\Rightarrow 6-x=0$

$\Rightarrow x=6$