Warm-ups! Every lamb has 4 legs. Every chicken has 2 legs. 1. How many legs do 5 lambs and 20 chickens have? 2. How many legs do 100 lambs and 27 chickens have? 3. How many legs do L lambs and C chickens have? 60 legs 454 legs 4l + 2c

Describing Patterns Section 1.2

Objectives for the day: Use variables to describe patterns in instances or tables Identify and apply the associative, commutative, and transitive properties Create expression to model real- world situations.

Definitions Term: Factor: Instance: Pattern: A group of terms which a connection or relationship can be found One term of a pattern A number, variable, or combination of the two A number of expression that is multiplied. *If a ∙ b = c, then a and b are factors of c. Ex. 5x 2 + 7x + 8y + 6 has4 terms

Evaluate each expression # (3 + 8) ÷ 3 2(4 + 8) ÷ 3 2(5 + 8) ÷ 3 Write another instance of the pattern (#4): 2 ( 9 + 8) ÷ 3 22/3 8 26/3

Give two instances of each pattern # 5: # 6: 4 x 3 = 4 ∙ x ∙ x ∙ x 4 (2) 3 = 4 ∙ 2 ∙ 2 ∙ 2 4(-3) 3 = 4 ∙ -3 ∙ -3 ∙ -3 Use the commutative property of multiplication to find another expression that gives the same value as 6a ∙ b b ∙ 6a 7 (4 + 3) = 7 ∙ (11 + 3) = 7 ∙ (x + 3) = 7 ∙ x + 21

Three instances of a pattern are given. Describe the pattern using one variable. 3 ∙ 1 – 7 = 3 (1 – 4) ∙ 11 – 7 = 3 (11 – 4) ∙ ¼ – 7 = 3 (¼ – 4) ∙ x – 7 = 3 (x – 4) + 5

Example 2 Jana designs and sells t-shirts online. She works through a company that pays her a base of $50 every month for her designs, plus a 20% profit for every t-shirt that is sold. Each shirt costs $20. #9: write an expression that calculates Jana’s monthly earnings if she sells s t-shirts. #10: How much does Jana make in a month when she sells 30 t-shirts? (20s) dollars (20 ∙ 30) dollars $170.00

Break up into groups of 4:

Homework Finish worksheet 1.2A Pages 16 – 17 1 – 22 (ex. Cred: 23)