# For those who don't know part 3 (Determinants)

Algebra Level 4

$X=\begin{vmatrix} 1 & 2 & 2 & 1 \\ 1 & 2 & 4 & 2 \\ 2 & 7 & 5 & 2 \\ -1 & 4 & -6 & 3 \end{vmatrix}$

Find the value of $$\det (X)$$.

If you don't know how to expand determinants, look at this wiki

Note: This problem isn't orginal.

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