Well, i can at least answer the factoring part of it.
24. 21+14
They want you to find a factor of these numbers. Basically find two number that when multiplied together equals 21/14
21 14
^ ^
7 3 7 2
Factor pairs= 7&3, 7&2
25.36+18
Same thing, factor pairs
36 18
^ ^
9 4 9 2
Factor Pairs= 9&4, 9&2