Does exist -- It only exists when the determinant does not equal zero.
Step-by-step explanation:
The inverse of a matrix is the transpose of the cofactor matrix, divided by the determinant. If the determinant is zero, the result of the division is undefined and the inverse does not exist.
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For this matrix, the determinant is (-2)(18) -(9)(4) = -72. The inverse exists.
I think the answer would be 56. Bc the first job has 8 different people who could get the job and then once someone is chosen for that slot the next teaching position only has 7 candidates. So you would take 8*7 which equals 56.
