560 is one such.
The difference is between factor pairs and distinct factors. With square numbers, one of the factor pairs will be the same number twice. When listing the distinct factors, that number is only listed once.
(y + 3)(y - 10)
The factor pairs of 20 are: 20,1 / 10,2 / 5,4
The factor pairs of 51 are (1,51) and (17,3)
The factor pairs of 10 are 1*10, 2*5
There are 10 factor pairs for 5,000:5000,12500,21250,41000,5625,8500,10250,20200,25125,40100,50
1 and 10 are a factor pair for 10.
1 and 10, 2 and 5
10x1 1x105x22x5
Two of them.
560 is one such.
2
There are 3 factor pairs of 20: 1 x 20, 2 x 10 and 4 x 5.
The factor pairs of 50 are: 1 x 50 2 x 25 5 x 10
The difference is between factor pairs and distinct factors. With square numbers, one of the factor pairs will be the same number twice. When listing the distinct factors, that number is only listed once.
Factor pairs are just the factors of a number listed in a different way. The factors of 20 are 1, 2, 4, 5, 10, 20 The factor pairs of 20 are (20,1)(10,2)(5,4)