SOLUTION: I was doing my assignment I got stuck on this problem. A repair service charges a fixed fee for a house call plus a fixed hourly rate. If a 2 hour call cost $57 and a 4 1/2 hour

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Question 105067: I was doing my assignment I got stuck on this problem.
A repair service charges a fixed fee for a house call plus a fixed hourly rate. If a 2 hour call cost $57 and a 4 1/2 hour call costs $97, what is the fixed fee for a house call.
I have:
2/57=4.5/97
194=256.5
Now what?
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Let x = the fixed fee and y = the hourly rate.
For the 2-hour call, you can write:
1) x+%2B+2y+=+57 ...and for the 4.5-hour call, you can write:
2) x+%2B+4.5y+=+97
You need to solve this system of equations for x, the fixed fee.
Solve equation 1) for y and substitute into equation 2) then solve it for x.
1) y+=+%28%2857-x%29%2F2%29
2) x%2B4.5%28%2857-x%29%2F2%29+=+97 Simplify and solve for x. Multiply both sides by 2.
2x%2B4.5%2857-x%29+=+194
2x%2B256.5-4.5x+=+194
-2.5x+=+-62.5
x+=+%28-62.5%29%2F-2.5
x+=+25
The fixed fee is $25.00
The hourly fee is:
y+=+%2857-x%29%2F2 Substitute x = 25.
y+=+%2857-25%29%2F2
y+=+32%2F2
y+=+16
The hourly fee is $16.00