(1, 21)
(3, 7)
(21,1)(7,3) (42,1)(21,2)(14,3)(7,6) Since 21 is a factor of 42, all the factors of 21 will be included in the factor pairs of 42.
The factor pairs of 210 are: 1 and 210, 2 and 105, 3 and 70, 5 and 42, 6 and 35, 7 and 30, 10 and 21, and 14 and 15. The factor pairs of 63 are: 1 and 63, 3 and 21, and 7 and 9.
The factor pairs of 21 are (21, 1) (7, 3) Even considering their negative counterparts, they don't add up to -13.
14 and 21, and 21 and 28 are the number pairs between 15 and 30 that have 7 as their greatest common factor.
The factor pairs of 51 are (1,51) and (17,3)
The factor pairs of 21 are:1, 213, 7Therefore, the number 21 has two pairs of positive integer factors.
There are two factor pairs of 21: 21 = 1 x 21 21 = 3 x 7
Factors of 21 are 1, 3, 7, and 21; the factor pairs are (1 x 21) and (3 x 7).
1 & 21, and 3 & 7
1 and 21, 3 and 7,
1,21 3,7
21,17,3
(21,1)(7,3)
(21,-1)(7,-3)(-21,1)(-7,3)
(21,1)(7,3) (42,1)(21,2)(14,3)(7,6) Since 21 is a factor of 42, all the factors of 21 will be included in the factor pairs of 42.
There are 3 factor pairs of 63: 63 = 1 x 63 63 = 3 x 21 63 = 7 x 9
Factor pairs of 42 are 1 x 42, 2 x 21, 3 x 14, and 6 x 7.