SOLUTION: Solve by the elimination method. 3r-7s=-35 7r+3s=73 If necessary what is the solution of the system? A. The solutions is ______. B. There are infinitely many solutions. C

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Question 452602: Solve by the elimination method.
3r-7s=-35
7r+3s=73
If necessary what is the solution of the system?
A. The solutions is ______.
B. There are infinitely many solutions.
C. There is no solution.

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by the elimination method.
3r - 7s = -35
7r + 3s = 73
:
Multiply the 1st equation by 3, multiply the 2nd equation by 7, resulting in:
9r - 21s = -105
49r+ 21s = 511
-----------------addition eliminates s, find r
58r = 406
r = 406%2F58
r = 7
:
Find s using the 2nd original equation
7(7) + 3s = 73
49 + 3s = 73
3s = 73 - 49
3s = 24
s = 24%2F3
s = 8
:
Check solutions of r=7 and s=8 in the 1st original equation
3(7) - 7(8) =
21 - 56 = -35