If \(\begin{vmatrix}-x & 12 \\-1 & 4 \end{vmatrix} = - 12\), find x.

Find the value of \(\begin{vmatrix}0 & 3 & 2 \\1 & 7 & 8 \\0 & 5 & 4\end{vmatrix}\).

How many sides has a regular polygon whose interior angle is 135°?

Find the mid point of S(-5, 4) and T(-3, -2)