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### Course: Algebra (all content)>Unit 1

Lesson 6: Introduction to equivalent algebraic expressions

# Equivalent expressions

In this math lesson, we learn how to find equivalent expressions by combining like terms and factoring. We start with an expression like x + 2 - y + x + 2 and simplify it by adding the x terms and factoring out common factors. This helps us compare expressions and solve problems more easily.

## Want to join the conversation?

• how should i remember order of ops (operations)?
• PEMDAS does really help. You can also remember it as please excuse my dear aunt sally.
• i see people using PEMDAS as order of operations. But what i learned was BEDMAS
Brackets
Exponents
Division
Multiplication
Subtraction
Im pretty sure it means the same thing but why does everyone have a different name for it?
• They are the same, but the two together show some good distinctions. Brackets [] and Parentheses () both have to include the other one because you could see both. It also reminds us that division and multiplication are on the same level, so generally done left to right. Also, addition and subtraction are on the same level left to right.
• I still don't get it..How can I learn this without having negative thoughts about how dumb I really am?
• It’s important to give yourself time, understanding math concepts is a matter of effort but also patience, don’t beat yourself down because you think you can’t do it, and ask questions if you get stuck
• what does sal mean when he said he can factor the two out? and how did he get one from the two?
• Factoring is the opposite of multiplying by distribution.
For example:
Multiplication: 2(5x+1) = 2(5x) + 2(1) = 10x+2
To factor, you reverse the process. You identify the common factor in both terms (the 2), you write the 2 in front and you divide each term by 2.
10x+2 = 2(10x/2 + 2/2) = 2(5x+1)

Notice, the 2/2 = 1, that is where the 1 is coming from in the video.

Hope this helps.
• I am probably being dumb right now, but I am confused. He said that at that when you factor out the 2 you get 1. Did he say that cuz 1+1=2?
• Not quite, it's because if you divide 2 by 2, you get 1. He was factoring out ech of the numbers by dividing them by 2. And you're not dumb, sometimes people just need a different explanation.
• In this math lesson, we learn how to find equivalent expressions by combining like terms and factoring. We start with an expression like x + 2 - y + x + 2 and simplify it by adding the x terms and factoring out common factors. This helps us compare expressions and solve problems more easily.
• I like tacos
• When he factors out the 2, he gets 1. I don’t quite understand how you got 1 by factoring out the 2!
• If you factor 2 from 2, you are dividing 2/2=1
• why do you have a 1 left over at ?
• When you multiply 2 by x and 2 by y and 2 by 1 you get 2x+2y+2. I hope that helps.
• Is a number with multiple letters accountable? (2jkl).
• What matters is the idea of a common factor , if you have:

2kjl +4kj +2 you can still factor this as : 2(kjl + 2kj +1) the expressions are still equivalent