Exercise 74 Page 227

The determinant of a matrix is found by subtracting the products of the diagonals. To evaluate the determinant of a 2* 2 matrix, we will use the appropriate formula. | cc a & b c & d | = ad-bcWe can substitute the values from the given matrix into this formula. | cc - 3 & - 5 - 1 & - 9 | = - 3(- 9)-(- 5)(- 1) Finally, we will simplify the numeric expression.

- 3(- 9)-(- 5)(- 1)

MultNegNegOnePar

- a(- b)=a* b

27-(- 5)(- 1)

MultNegNegTwoPar

(- a)(- b)=a* b

27-5

SubTerm

Subtract term

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