SOLUTION: Use cramer's rule to solve the following system of equations. 5x-2y=19 7x+3y=15

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Question 1077537: Use cramer's rule to solve the following system of equations.
5x-2y=19
7x+3y=15
Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!
Putting the equations into matrix form, Ax = B, we get:

+x%5Bi%5D+=+det%28A%5Bi%5D%29%2Fdet%28A%29+ where A%5Bi%5D is A with column i replaced by B
det(A) = 5*3-(-2*7) = 15+14 = 29
det(A1) = 19*3-(15*-2) = 57-(-30) = 87
det(A2) = 5*15-(7*19) = 75 - 133 = -58
+x%5B1%5D+=+87%2F29+=+3+
+x%5B2%5D+=+-58%2F29+=+-2+
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Ans: +highlight%28x+=+%28matrix%282%2C1%2C+3%2C-2%29%29%29+
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I checked it, but you can also check that Ax = B, or you can plug into the original equations (x=x1, y=x2).