Name:			Date:
Evaluate Determinants of 2x2 Matrices

1) $\left[\begin{array}{cc}6& 10\\ 9& 2\end{array}\right]$	2) $\text{evaluate:}\left|\begin{array}{cc}7& 10\\ 5& 4\end{array}\right|+\left|\begin{array}{cc}8& 4\\ -2& 10\end{array}\right|$
3) $\left[\begin{array}{cc}0& -2\\ 6& -5\end{array}\right]$	4) $\left|\begin{array}{cc}9& -2\\ -5& 4\end{array}\right|$
5) $\left|\begin{array}{cc}4& -2\\ -1& 5\end{array}\right|$	6) $\text{evaluate:}\left|\begin{array}{cc}7& 10\\ 6& 7\end{array}\right|+\left|\begin{array}{cc}3& 4\\ -3& 2\end{array}\right|$
7) $\left|\begin{array}{cc}-6& 3\\ 2& 4\end{array}\right|$	8) $\left[\begin{array}{cc}8& 2\\ 3& 4\end{array}\right]$
9) $\left[\begin{array}{cc}-5& 2\\ 1& -2\end{array}\right]$	10) $\left|\begin{array}{cc}-5& 3\\ 4& 2\end{array}\right|$
11) $\left|\begin{array}{cc}-4& 6\\ 2& 5\end{array}\right|$	12) $\left|\begin{array}{cc}0& 4\\ -5& 0\end{array}\right|$
13) $\left[\begin{array}{cc}-6& 2\\ 1& -4\end{array}\right]$	14) $\left[\begin{array}{cc}-10& 4\\ 0& -5\end{array}\right]$
15) $\left[\begin{array}{cc}-20& 2\\ -4& 3\end{array}\right]$	16) $\left|\begin{array}{cc}2& -4\\ 5& -3\end{array}\right|$
17) $\left|\begin{array}{cc}2& 5\\ -5& 0\end{array}\right|$	18) $\left[\begin{array}{cc}-6& 2\\ -9& 10\end{array}\right]$
19) $\left[\begin{array}{cc}1& -10\\ 5& -2\end{array}\right]$	20) $\left[\begin{array}{cc}2& -7\\ 9& -4\end{array}\right]$

 

Answers:

1) $-78$	2) $66$
3) $12$	4) $26$
5) $18$	6) $7$
7) $-30$	8) $26$
9) $8$	10) $-22$
11) $-32$	12) $20$
13) $22$	14) $50$
15) $-52$	16) $14$
17) $25$	18) $-42$
19) $48$	20) $55$