SOLUTION: If I use the Cramers rule to solve the equation, how do I solve the problem? 5x+3y=7 4x+5y=3

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Question 176600: If I use the Cramers rule to solve the equation, how do I solve the problem?
5x+3y=7
4x+5y=3
Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
Cramers rule takes the format of
:
lets call %28matrix%282%2C2%2C5%2C3%2C4%2C5%29%29 matrix A. you find x by taking the determinant of matrix A(with the first column replaced by the answer matrix) divided by det of matrix A.
:
%28matrix%282%2C2%2C5%2C3%2C4%2C5%29%29%28matrix%282%2C1%2Cx%2Cy%29%29=%28matrix%282%2C1%2C7%2C3%29%29 where x and y are your unknowns.
:
det A(1st column replaced)%28matrix%282%2C2%2C7%2C3%2C3%2C5%29%29= 7(5)-3(3)= 35-9=26
det A =%28matrix%282%2C2%2C5%2C3%2C4%2C5%29%29=25-12=13
:
x= det A(1st column replaced)/det A=26/13=highlight%282%29
:
you find y by taking the determinant of Matrix A(with the 2nd column replace by the answer matrix) divided by det of matrix A
:
det A(2nd column replaced)%28matrix%282%2C2%2C5%2C7%2C4%2C3%29%29= 5(3)-7(4)=15-28=-13
:
y= det A(2nd column replaced)/det a=-13/13=highlight%28-1%29