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January 12th, 2016, 06:24 PM   #1
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Year 11 algebra

x + 2y = 4
2x + 3y = 10

I am really stuck!

Last edited by skipjack; January 13th, 2016 at 04:58 AM.
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January 12th, 2016, 06:34 PM   #2
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Multiply the first equation by 2 and subtract the second equation from the result. That gives you y and x should be easy to find from there.
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January 12th, 2016, 06:35 PM   #3
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When you mean multiply, do you also mutiply the answer of the 1st equation aswell?
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January 12th, 2016, 06:59 PM   #4
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Yes.
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January 12th, 2016, 06:59 PM   #5
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Quote:
Originally Posted by Fastsad View Post
When you mean multiply, do you also mutiply the answer of the 1st equation aswell?
Multiply every term in the 1st equation by 2 ...

2x+4y=8
2x+3y=10

now, subtract each term in the 2nd equation from the 1st
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January 13th, 2016, 02:36 AM   #6
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This is a simultaneous equation that can be solved either by

1. elimination (the methods Skeeter and Greg are suggesting); or
2. substitution


I made a post a few days ago here:

I have to solve 3 equations with 3 variables and I'm extremely confused

that explains both methods. You can also try the link by Denis on that thread.
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