Algebraic Expressions Lesson 3.3 Algebraic Expressions

Definitions In your math notebook, define the following word: Algebraic expression – an expression that contains a variable. For example, if Maria is 2 inches taller than Joe and if the variable M represents Maria’s height, then the algebraic expression M – 2 represents Joe’s height. Evaluate an expression – similar to writing a special case for a general pattern—you will replace the variable with a specific value

Math Message Using your definitions, answer the following question: John is 4 years older than Mike. How old is John?

Math Message Follow-Up One way to represent John’s age is to write an algebraic expression in which a variable stands for Mike’s age. For example, if m represents Mike’s age in years, then m + 4 represents John’s age An algebraic expression is a group of symbols that states a relationship between quantities and contains at least one variable. It may also contain numbers, operation symbols (+, -, *, /), and grouping symbols (such as parentheses)

Let’s try these examples… Chan weights 15 pounds less than Henry. If h = Henry’s weight then h – 15 represents Chan’s weight. Janice has twice as many stamps in her collection as Santiago. If s = the number of stamps in Santiago’s collection, the 2 * s or 2s, represents the number of stamps in Janice’s collection. There were one-third as many tests in history class as in Spanish class. If t = the number of tests in Spanish class, then there were 1 3 ∗𝑡, 𝑜𝑟 1 3 𝑡, 𝑜𝑟 𝑡 3 tests in history class.

With a Partner… Complete pages 89 and 90 MAKE SURE TO READ THE PROBLEM CORRECTLY IN ORDER TO HAVE THE RIGHT ALGEBRAIC EXPRESSION

Homework Math Boxes 3.3 Study Links 3.3