Mathematical+Reflections,+p.+52+0809

April 1st, 2009 YMJ

__ Big Idea __ : Equations can be used to model real things. __ Essential Question __ : What are the distributive and commutative properties used for? Notes:

Mathematical Reflections #3

1. Explain how the distributive and commutative properties can be used to write equivalent expressions. Use example to illustrate your explanations.

The distributive property can be used to write equivalent expressions. For example, x(4+2), (4x+2x) The commutative property can be used to write equivalent expressions. For example, 2+3 can be 3+2

2. a. Give an example of a real-life situation that can be represented by at least two equivalent expressions. Explain how each expression represents the situation.

X2+6X+8

b. Use the distributive and commutative properties to show that the expressions are equivalent.

Distributive property (X+2) (X+4) = X2+6X+8

Commutative property (X+4) (X+2) = X2+6x+8

Summary

Distributive and Commutative properties are different and I learned how they are different