Question

what is the fact family for 10, 7 and 8

Answer 1

There could be two fact families.

10 = 7 + ?
10 = ? + 7
10 - ? = 7
10 - 7 = ?

10 = 8 + ?
10 = ? + 8
10 - ? = 8
10 - 8 = ?

I hope this helps.