Solve using Determinants and Cramer's Rule?

[euphoriae]

Homework Statement

I was absent and missed the lecture on Cramer's rule and Determinants and have no idea how to start the homework..

The directions and problem are as follows:

Using Cramer's Rule, set this problem up to find "a". Only evaluate the Denominator. When finished with the Denominator, finalize the answer by putting it into the context: a=?/#

6a -4b -5c -2d = -5
-7a +3b + c -3d = -6
2a - 6b + 4c + 9d = 9
4a + 7b - 8c -5d = -2

Thanks in advanced!
2. The attempt at a solution

I honestly have no idea even where to start.. if someone could help get me started off that would be great.

Thanks!

 

[micromass]

Can you tell us what Cramer's rule states?