L. Fact Families
Mara and Emily recorded the fact family for 0, 3, and 3.
Mara’s work Emily’s work
3 − 0 = 3 3 − 0 = 3
0 − 3 = 3 3 + 0 = 3
3 + 0 = 0 0 + 3 = 3
0 + 3 = 3 3 − 3 = 0
Mara and Emily noticed that their work did not match. Who is right? How do you know?