<< Back to Lessons Index

7th Grade Math / Lesson 3: Properties

 PROPERTIES What will we be learning in this unit? This lesson will explain the different properties for adding and multiplying. Vocabulary words are found in this purple color throughout the lesson. Remember to put these in your notebook.

 Properties Commutative Property The commutative property for addition says that the order in which you add numbers does not matter.Ex) 6 + 7 = 7 + 6 The commutative property for multiplication says that the order in which you multiply numbers does not matter.Ex) 4 * 2 = 2 * 4

 Properties Associative Property The associative property for addition says that the way you group numbers to be added does not matter. Ex) (65 + 21) + 33 = 65 + (21+ 33) The associative property for multiplication says that the way you group numbers to be multiplied does not matter. Ex) (5 * 2) * 6 = 5 * (2 * 6)

 Properties Distributive Property The distributive property is when you take a factor and spread it out over a sum (or difference).Ex) 2 ( x + 4 ) = 2 * x + 2 * 4 = 2x + 8 Ex) 5 ( 4 - x ) = 5 * 4 - 5 * x = 20 - 5x

 Properties Identity Property The identity property for additionsays that zero added to another number is always the other number.Ex) 12 + 0 = 12 The identity property for multiplication says that one multiplied by any number is always the other number.Ex) 35 * 1 = 35

 Properties Zero Property of Multiplication The zero property of multiplication says that when you multiply by zero, the result is zero.Ex) -64 * 0 = 0Ex) 0 * 47 = 0

 Properties Inverse Property The inverse property of addition says that when you add opposites the result is always zero.Ex) -64 + 64 = 0The inverse property of multiplication says that when you multiply reciprocals* the result is one.Ex)     4/5 *5/4      = 1* reciprocals are the numbers you get when you flip a number. In other words you take the numerator and make it the denominator and take the denominator and make it the numerator. 2 and  ½ are reciprocals.

 Properties For a self-check on identifying the properties, click  HERE. Close the page by clicking on the x in the top right corner when you are ready to return to the lesson slide.