4 (the square of 2) and 36 (the square of 6) add up to 40.
40
4, 9, 16, 25, and 36 are the square numbers between 1 and 40.
41 & 39 = 1599. (40 x 40 = 1600 but I assume you meant different numbers)
52
Not at all. For example: gcf(101, 102) = 1 gcf(40, 80) = 40
1,4,9,25,36
40
42
7 squared and 3 squared. 49 - 9 = 40
4, 9, 16, 25, and 36 are the square numbers between 1 and 40.
30 and 40
12 and 252 is a pair of numbers that fit those criteria.
20 and 20.
20 and 40
8
Let's denote the two square numbers as x^2 and y^2. The difference between two square numbers can be expressed as (x^2 - y^2), which can be factored into (x + y)(x - y). Since the difference is 80, we have (x + y)(x - y) = 80. The factors of 80 are 1, 2, 4, 5, 8, 10, 16, 20, 40, and 80. By testing out different combinations of these factors, we find that the pair of square numbers that make a difference of 80 is 82^2 and 2^2.
27 and 81 are a possibility. Also numbers like 5 and 10, 20 and 40.