Question 607587: Please solve.
3x = y + 5
x + 2y = 4
My answer is y=1, x=2 (apparently I solve differently than my son's teacher)
Found 2 solutions by rfer, solver91311:
Answer by rfer(16322)   (Show Source):
You can put this solution on YOUR website! 3x=y+5 same as y=3x-5
x+2y=4
x+2(3x-5)=4
x+6x-10=4
7x=14
x=2
--------------
2+2y=4
2y=2
y=2/2
y=1
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3*2=5+1
I get the same as you do.
Bob
Answer by solver91311(24713)  (Show Source):
You can put this solution on YOUR website!
Can't say what the teacher is doing wrong, if anything.  and  is correct, and given error free arithmetic should be the result of any solution method: Substitution, Elimination, Gauss-Jordan Row Reduction, and/or Cramer's Rule. Which is the case; I checked.
The problem could be that the teacher has specified a way of presenting the solution. I.e. s/he may want the answer in ordered pair form or perhaps even in solution set form:
Ordered pair:
)
Solution set
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Then again, it wouldn't be the first time that a teacher, textbook, and/or answer key was wrong. Won't be the last time either.
John
My calculator said it, I believe it, that settles it
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