SOLUTION: Please Help :( Use Cramers Rule to solve for y: x-4y=4 4x-y=1 Thank:)

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Question 39273: Please Help :(
Use Cramers Rule to solve for y:
x-4y=4
4x-y=1
Thank:)
Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
+matrix%282%2C2%2C%0D%0A1%2C-4%2C%0D%0A4%2C-1%29+

D = (-1) - (-16)
D = -1+16
D = 15

Now, Dx = +matrix%282%2C2%2C%0D%0A4%2C-4%2C%0D%0A1%2C-1%29+

Dx = (-4) - (-4)
Dx = -4 + 4
Dx = 0

and Dy = +matrix%282%2C2%2C%0D%0A1%2C4%2C%0D%0A4%2C1%29+

Dy = 1 - 16
Dy = -15

So, x = Dx/D
x = 0/15
x = 0

and y = Dy/D
y = -15/15
y = -1

CHECK:
x-4y should be 4
0-4(-1)
4... correct

4x-y should be 1
0-(-1)
1... correct

jon.