Question

th 1b (section 5) (dual credit - little chut
** determinants, matrices, and cramers
evaluate the determinant.
$\

$$\begin{vmatrix} 7 & 7 \\\\ 3 & 9 \\end{vmatrix}$$

$
$\

$$\begin{vmatrix} 7 & 7 \\\\ 3 & 9 \\end{vmatrix}$$

=\square$

Explanation:

Step1: Recall 2x2 determinant formula

For

$$\begin{vmatrix} a & b \\ c & d \end{vmatrix}$$

, determinant = $ad - bc$

Step2: Substitute values into formula

$

$$\begin{vmatrix} 7 & 7 \\ 3 & 9 \end{vmatrix}$$

= (7 \times 9) - (7 \times 3)$

Step3: Calculate the result

$= 63 - 21$

Answer:

42