SOLUTION: 2r - 3s = 12 3r + 2s = 31 solve by the elimination method what is the solution of the system (type an ordered pair. Use the intergers or fractions for any numbers in the exp

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Question 321075: 2r - 3s = 12
3r + 2s = 31
solve by the elimination method
what is the solution of the system
(type an ordered pair. Use the intergers or fractions for any numbers in the expression)
this question is on my final exam please help and quick thank you!!!!!!!!!!!!!!!!

Gabriella
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
2r - 3s = 12
3r + 2s = 31
solve by the elimination method
:
Multiply the 1st equation by 2, multiply the 2nd equation by 3, results:
4r - 6s = 24
9r + 6s = 93
----------------Addition eliminates s, find r
13r = 117
r = 117%2F13
r = 9
:
Use the 2nd original equation to find s, substitute 9 for r
3(9) + 2s = 31
27 + 2s = 31
2s = 31 - 27
2s = 4
s = 4%2F2
s = 2
:
The r,s ordered pair: 9, 2
:
:
Check solutions in the 1st original equation, substitute for r and s
2r - 3s = 12
2(9) - 3(2) =
18 - 6 = 12, confirms our solutions