precal
posted by Anonymous .
okay, so I'm trying to figure out how to do this 3x3 matrix. I'm suppose to be finding the determent and using CRAMER'S RULE. Can someone please explain to me how to do this?
4xy+z= 5
2x+2y+3z=10
5x2y+6z=1


first determinant calculator
http://www.wolframalpha.com/widgets/view.jsp?id=7fcb0a2c0f0f41d9f4454ac2d8ed7ad6
+4 1 +1
+2 +2 +3
+5 2 +6
determinant = D = 55 
Now for x put right side in x column
+5 1 +1
10 +2 +3
+1 2 +6
determinant = Dx = 125
x = 125/55
You go ahead and do y and z 
Utube on how to find determinant of 3x3
http://www.youtube.com/watch?v=ROFcVgehEYA&feature=related 
Now for x put right side in x column
5 1 +1 nope negative 5
10 +2 +3
+1 2 +6
determinant = Dx = 55
x = 55/55
x = 1
You go ahead and do y and z