Question

Evaluate the determinant of each matrix

-3 2 -3
0 -1 -1
3 0 -3

My answer is -36
The correct answer is -24 but I don't understand how they got the answer.

Answer 1

The algorithm I use sets it up this way:

D = -3(3-0) - 2(0 - (-3)) - 3(0 - (-3))
= -9 -6 - 9
= -24

KhanAcademy shows 2 basic methods

https://www.khanacademy.org/math/algebra-home/alg-matrices/alg-determinants-and-inverses-of-large-matrices/v/finding-the-determinant-of-a-3x3-matrix-method-2

https://www.khanacademy.org/math/algebra-home/alg-matrices/alg-determinants-and-inverses-of-large-matrices/v/finding-the-determinant-of-a-3x3-matrix-method-1