1. ## Matrix

Can someone give me a hand with this one?

Find the determinate of the matrix
{8+4a 4}
{5+3a 3}

Possible solutions:
4
44
4+24a
44+24a

2. Originally Posted by gretchen
Can someone give me a hand with this one?

Find the determinate of the matrix
{8+4a 4}
{5+3a 3}

Possible solutions:
4
44
4+24a
44+24a
The determinant of a 2x2 matrix is defined to be ad - bc;

((8 + 4a)*(3)) - ((4)(5 + 3a))

(12*a + 24) - (12a + 20)

= 4