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nicmike04
Oct 30, 2008, 11:43 AM
Thank you for answering my question, but it really did not help I will give you an example of the problem that I have

x+2y=1
3x-y=10

I cannot figure out how to solve this at all. I have used all of the Google search engines to try to figure it out and it is not helping..

Someone please help me!

Thank you,
Nicole

Unknown008
Oct 31, 2008, 01:57 AM
Substitution is a method where you have to 'replace' one variable into an equation so that only one variable is left. So, in your question;

x+2y=1
3x-y=10

There are numerous ways to solve this problem with substitution. Let's do the simplest.

x+2y=1

Make x subject of formula,

x = 1-2y

Now, you, in a way, 'know' what x is. Since you 'know', plug it in your second equation!

3(1-2y)-y=10

You see? I replaced 'x' by its equal equation, that is '1-2y'. Now, you can solve the equation, find 'y' and solve for x using the first equation!

Hope it helped you, post back if you need more explanation:). However I think I was clear enough.

mariarosamaripo
Jan 6, 2009, 09:38 PM
2x-3=-y
3x+5y=2

mariarosamaripo
Jan 6, 2009, 09:42 PM
I need help with substitution
:confused:

Unknown008
Jan 8, 2009, 01:21 AM
Next time Maria, start a new thread for your question.

Substitution is a simple way to solve equations. You only need to choose a variable, and replace it in the other equation.

For example, make 'y' in 2x-3=-y, the subject of that formula.

Post back, then we'll go on.

juhi2011
Jan 8, 2009, 01:28 AM
3(1-2y)-y=10
the equation becomes a linear equation, use your brain in the same direction to get the answer, I hope this will help you