MHB Simplifying and expanding expressions

AI Thread Summary
The discussion focuses on simplifying and expanding algebraic expressions in preparation for a test. Participants provide examples, such as combining like terms in expressions like 4x + 7x - 5x, which simplifies to 6x. They also explain the importance of identifying like terms, emphasizing that terms with the same variables raised to the same powers can be combined. Additionally, they discuss the use of brackets in expressions, demonstrating how to expand them, such as (x+y)(x+y) resulting in x² + 2xy + y². Overall, the conversation aims to clarify the processes of simplification and expansion for better understanding.
litchris
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I have a test on simplifying and expanding expressions, could someone help me with this. I don't understand the formula and the way you do it
 
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Do you have specific examples of expressions requiring expansion and/or simplification?

Post a few you have attempted, showing how you tried them yourself ... help us help you.
 
i tried 4x+7x-5x and 4x^2-2xy-3y^2+6xy+3y^2-x^2 totally confused.
 
you can sum like terms ...

4x, 7x and -5x are all like terms $\implies 4x + 7x - 5x = 11x - 5x = 6x$

for the second, like terms have the same variables to the same power. like terms have the same color in the expression below ...

${\color{red}4x^2} {\color{blue}-2xy} {\color{green}-3y^2}{\color{blue}+6xy}{\color{green}+3y^2}{\color{red}-x^2} $

I assume you know how to sum terms with the same and/or different signs
Why don't you try and combine them ...

have a look at the link, too
https://www.mathsisfun.com/algebra/like-terms.html
 
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Thanks skeeter this helps
 
Would you use brackets in your test? In that case...

You multiply each number in the brackets by the other brackets for example: [ (x+y)(x+y) ] would equal [ x2 + xy + xy + y2 ]. Simplifying these expressions would equal x2 + 2xy + y2

Or...

As Skeeter said you combine the expressions from different sides to make a final answer.

4x+7y+2x+9y = 6x + 16y

These are purposely easier just for you to get the gist :)
 
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