Intro 2+5+x-7+x When you see this equation, you may be confused. What should I add? How do I add? What’s the answer?…
I can help you answer the first question. The first thing that may stand out to you are the two variables, x. If you’re guessing that we are going to add them, bingo!
Well, how do we add them together? We can add them easily, since x=1x. You may be wondering where the 1 popped up. There is actually an ‘invisible’ 1 hiding in the x! Remember: 1 times any number equals the same number, therefore the value of x will not be affected by multiplying 1.
Now, why can’t we add 2 plus x? We can’t add them because the two are not like terms. If we try adding them together, it would be 2x, which does not make sense, since 2x= x+x, not 2+x.
Before we add the two x’s together, let’s move the variables to one side and the digits on the other.
Before: 2+5+x-7+x After: 2+5-7+x+x
Question: How did we move all the digits on one side? We moved -7 or negative seven forward and moved +x backward to where -7 was before. Now, we can add and subtract the numbers and variables separately and not get confused.
Let’s add!
2+5=7
7-7=0
x+x=2x
0+2x=2x
Our simplified answer to the equation is 2x! Now that you learned a little bit about simplifying expressions, try some on your own!
https://quizizz.com/admin/quiz/5c388cc9082e07001af947b0/adding-subtracting-algebraic-expressions
Some of these questions may look tricky, but it’s actually very simple. Remember to refer back to this article if you don’t remember a step or confused!
良いね😊。