2. Sections 1.1: Patterns and Expressions  Goal: To identify and describe patterns

3. Sections 1.1: Patterns and Expressions  Variable : a symbol, usually a letter, that represents one or more numbers  Ex: x y n  Numerical expression : a mathematical phrase that contains numbers and operation symbols  Ex: 11 – (6 – 9)  Algebraic Expression : a mathematical phrase that contains one or more variables  Ex: 8 y + 17

4. Sections 1.1: Patterns and Expressions  Examples: 1. These figures are made with toothpicks. A. How many toothpicks are in the 20 th figure? Use a table of values with a process column to justify your answer. B. What expression describes the number of toothpicks in the n th figure?

5. Sections 1.1: Patterns and Expressions  Examples: 2. You buy a bag of fish food and some goldfish. The graph shows the total cost depending on how many goldfish you buy. What is your total cost if you buy the food plus 9 goldfish? Use a table to find the answer.

6. Sections 1.1: Patterns and Expressions  Homework:  Pg. 7 #8-42 (even)