Lesson 15: Simplify Algebraic Expressions6.AT.7

I can…

I can simplify algebraic expressions by combining like terms.

Key words

• Simplify Algebraic Expressions — Make an expression shorter. It keeps the same value.
• Like Terms — Terms with the same letter and the same power.
• Combine — Add or subtract terms with the same letter into one.
• Simplify — Write it in a smaller form with the same value.
• Coefficient — The number in front of a letter, like 3 in 3x.
• Term — A part of an expression, split off by + or −.
• Distributive property — Multiply by each part inside the ( ).

Steps

1. The rooms need microphones and stands: (4 + 2 + 6) microphones and (3 + 5 + 1) stands.
2. Microphones are like items, so I add: 4 + 2 + 6 = 12 microphones.
3. Stands are like items, so I add: 3 + 5 + 1 = 9 stands.
4. In algebra this is the same as 4m + 2m + 6m + 3s + 5s + 1s = 12m + 9s.

Try it

Dad writes 4y + 2 + 5y + 6 for the cost of his grocery list. Simplify 4y + 2 + 5y + 6.

Check your answer

9y + 8

4y + 5y = 9y and 2 + 6 = 8, so the simplified expression is 9y + 8.

Sentence starter

I know ___ because ___.

Goal: I can explain my steps using the words like terms, combine, simplify, and coefficient.