SOLUTION: Solve using Cramer's Rule. x+2y=5 -3x+y=11

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Question 112483: Solve using Cramer's Rule.
x+2y=5
-3x+y=11

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
I'm going to assume that you can evaluate a 2X2 determinant. If you can't, write back and we'll talk about that.

D=%28matrix%282%2C2%2C1%2C2%2C-3%2C1%29%29=%281%29-%28-6%29=7 (A 2X2 matrix consisting of the coefficients)

D%5Bx%5D=%28matrix%282%2C2%2C5%2C2%2C11%2C1%29%29=%285%29-%2822%29=-17 (The 2X2 matrix from above, replacing the x coefficients with the constant values)

D%5By%5D=%28matrix%282%2C2%2C1%2C5%2C-3%2C11%29%29=%2811%29-%28-15%29=26 (The 2X2 matrix from above, replacing the y coefficients with the constant values)

Cramer's Rule says, x=D%5Bx%5D%2FD and y=D%5By%5D%2FD, so x=-17%2F7 and y=26%2F7