Placing a question mark at the end of a phrase does not make it a sensible question. There is insufficient information for us to answer this question. Please edit the question to describe what it is that you want answered.
5 & 21
The numbers are 15 and 1
The two square numbers that have a difference of 9 are 25 and 16. This can be expressed as (5^2 = 25) and (4^2 = 16). The difference between them is (25 - 16 = 9).
16 and 20
16 and -5
eight times two equals 16
11 and 5
7 & 9
5 & 21
16 and 35
The numbers are 15 and 1
10 and 6
The smaller number is (74-16)/2 = 58/2 = 29
16 and 20
16 and -5
16 and 21
7 and 9