Solving systems of equations by elimination
- Thread starter koffii71
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Where are you stuck? You did the obvious subtraction, and... then what?
Please be complete. Thank you!
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Okay; you're wanting to add instead of subtract. That's fine. You multiplied one of the equations by -1 to create the opposite-sign terms and... then what?
Bob Brown MSEE
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By Elimination?
Your question asked how to use elimination.
From the first equation get 9y = 25-2x
Then "eliminate" the 9y in the second equation, by replacing
9y with (25-2x)
You will then be able to solve for x
Your question asked how to use elimination.
From the first equation get 9y = 25-2x
Then "eliminate" the 9y in the second equation, by replacing
9y with (25-2x)
You will then be able to solve for x
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FYI: In many ("most"?) books, this replacement, being a substitution, is called the method of substitution. "Elimination" means "setting up the equations so you can add down and eliminate one of the variables".
Bob Brown MSEE
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Correction
You are right. I believe 100%. Especially in the context of Augmented Matrices.
Adding equals to equals with the intent to eliminate, in the algebraic context.
Thanks for the correction
The method that I used is indeed called substitution.
Oh, Yes,FYI: In many ("most"?) books, this replacement, being a substitution, is called the method of substitution. "Elimination" means "setting up the equations so you can add down and eliminate one of the variables".
You are right. I believe 100%. Especially in the context of Augmented Matrices.
Adding equals to equals with the intent to eliminate, in the algebraic context.
Thanks for the correction
The method that I used is indeed called substitution.