SOLUTION: How do I solve for x and y in this problem? Can there be 2 answers? ax+by=r ax+cy=s

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Question 593453: How do I solve for x and y in this problem?
Can there be 2 answers?
ax+by=r
ax+cy=s
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for y:
1) ax%2Bby+=+r
2) ax%2Bcy+=+s Subtract equation 2) from equation 1) to get:
3) by-cy+=+r-s Factor a y from the left side.
3a) y%28b-c%29+=+r-s Finally, divide both sides by ( b-c).
3b y+=+%28r-s%29%2F%28b-c%29 Substitute this for y into equation 1).
1a) ax%2Bb%28%28r-s%29%2F%28b-c%29%29+=+r Solve for x:
x+=+%28r%2Fa%29+-+%28b%2Fa%29%28%28r-s%29%2F%28b-c%29%29 This is one solution for x.
If you substitute for y into equation 2), you get:
x+=+%28s%2Fa%29-%28c%2Fa%29%28%28s-r%29%2F%28c-b%29%29 which can be simplified to:
x+=+%28s%2Fa%29-%28c%2Fa%29%28%28r-s%29%2F%28b-c%29%29