Multiplication What are the properties of multiplication? identity zerocommutative distributive
What does 3 x 1 mean? 3 groups of 1 identity How can I make 3 groups of 1 with these counters?
What does 1 x 3 mean? 1 group of 3 identity How can I make 1 group of 3 with these counters?
What does 3 x 0 mean? 3 groups of 0 Zero property How can I make 3 groups of 0 with these counters?
What does 0 x 3 mean? Zero property How can I make 0 groups of 3 with these counters?
What does 3 x 4 mean? 3 groups of 4 How can I make 3 groups of 4 with these counters?
Could I use 3 and 4 another way and still get 12? What if I said 4 x 3. Would that work? commutative
4 x 3 4 groups of 3 How can I make 4 groups of 3 with these counters?
Could I rewrite 3 x 4 another way? What if I said (3 x 2) + (3 x 2). Would that work?
(3 x 2) + (3 x 2) distributive Which number did we Karate chop?
Could I rewrite 3 x 4 another way? What if I said (3 x 1) + (3 x 3). Would that work?
(3 x 1) + (3 x 3) distributive Which number did we Karate chop?
Could I rewrite 3 x 4 another way? What if I said (3 x 0) + (3 x 4). Would that work?
(3 x 0) + (3 x 4) Which number did we Karate chop? distributive
Do you think that would work for other numbers? 5? 6? 7? 8? 9? 10? 11? 12?
Let’s think about ways to break apart numbers… This is how we might break the number 6 into 2 numbers… This is how we might break the number 6 into 2 numbers… How might we break up 7? How might we break up 7? How might we break up 8? 9? How might we break up 8? 9?
Let’s look at 7 x 3. I can draw an array like this… OR I can use my facts that I already know to solve this problem. Could I break a 7 into a 5 and a 2?
I still have 7 groups of 3, but now I am showing them as 5 groups of 3 and 2 more groups of
= 21 7 x 3 = 21
Without an array I can solve it like this….
Distributive Property Set-up Copy this set-up into your journal: (_____ x ______) + (_____ x ______) Remember: you only decompose one number! Ex: 4 x 8 = (4 x 5 ) + (4 x 3) (We decomposed the 8 into 5 and 3) = = 32
Did we decompose the 8 or the 3?
How did we decompose it? =24 8 x 3 = 24
How did we decompose it? =
= ______ 6 Try this one on your own. Use the array below if you need help.
7 = ______ Try this one on your own. Use the array below to help if you need it.