SOLUTION: solve using the elimination method 5r-6s=-5 6r+5s=55 The answer should be an ordered pair and either an integer or fraction.

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Question 220967: solve using the elimination method
5r-6s=-5
6r+5s=55
The answer should be an ordered pair and either an integer or fraction.
Found 2 solutions by drj, checkley77:
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
solve using the elimination method
5r-6s=-5 Equation A
6r+5s=55 Equation B

Multiply Equation A by 5 and Equation B by 6
25r-30s=-25 Equation A1
36r+30s=330 Equation B1

Add equations A1 and B1 to eliminate s-terms.

61r=305 or r=305/61=5

Then Equation A yields 5*5-6s=5 or 25-6s=-5 or s=5

ANSWER: The solution is r=5 and s=5 or (5,5). Checking via substitution method.

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
We'll use substitution. After moving -30*s to the right, we get:
25%2Ar+=+-25+-+-30%2As, or r+=+-25%2F25+-+-30%2As%2F25. Substitute that
into another equation:
36%2A%28-25%2F25+-+-30%2As%2F25%29+%2B+30%5Cs+=+330 and simplify: So, we know that s=5. Since r+=+-25%2F25+-+-30%2As%2F25, r=5.

Answer: system%28+r=5%2C+s=5+%29.



I hope the above steps were helpful.

And good luck in your studies!

For free Step-By-Step Videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra or for Trigonometry visit http://www.FreedomUniversity.TV/courses/Trigonometry.

Respectfully,
Dr J

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
5r-6s=-5 MULTIPLY BY 5
6r+5s=55 MULTIPLY BY 6 & ADD.
-------------------------------------------
25R-30S=-25
36R+30S=330
-------------
61R=305
R=305/61
R=5 ANS.
5*5-6S=-5
25-6S=-5
-6S=-5-25
-6S=-30
S=-30/-6
S=5 ANS.
PROOF:
6*5+5*5=55
30+25=55
55=55