standard_description: Apply properties of operations as strategies to add and subtract. (Students need not use formal terms for these properties.) Examples: If 8 + 3 = 11 is known, then 3 + 8 = 11 is also known. (Commutative property of addition.) To add 2 + 6 + 4, the second two numbers can be added to make a ten, so 2 + 6 + 4 = 2 + 10 = 12. (Associative property of addition.)
problem_activity: Task
For each set of numbers below, pick two numbers that add to make six. Write an equation that shows that those two numbers add to make 6.
3,    5,     3
6,     0,     2
1,     6,     5
3,     2,     4
4,     2,     6


aligns: no