please evaluate the determinant of the given matrix

Question

[7,-5, 2, -4, 9, -4, 0, 6, 10]

Answer 1

The determinant of

 7  -5   2

-4   9  -4

 0   6   10

is easily calculated by expanding along the third row as

-6((7)(-4)-(-4)(2))+10((7)(9)-(-4)(-5)=-6(-20)+10(43)=550

Answer 2

There are 9 elements in the set, it it forms 3 x 3 matrix as the following,

 

 

 7   -5   2 |  7  -5

-4    9  -4 | -4   9

 0    6  10 |  0   6

 

then the determinant = 7(9)(10)+(-5)(-4)(0)+(2)(-4)(6) - (-5)(-4)(10) - (7)(-4)(6) - (2)(9)(0) 

                               =  630 + 0 - 48 - 200 + 168 -0

                                = 550

Answer 3

Determinant is for square matrix.