Because 10 is a multiple of 5.
2 x 5 = 10
-5 and -10
5, 10, 15, 20 and 25
3
The numbers are 2 and -5
the multiplies of 5 are just in the 5 times tables like 5x5=25
65
the first 5 multiplies of 5 are 5, 10, 15, 20, 25
5 10 15 20 25 30
3 and 7 multiplies to 21 and equals to 10
110
-10 and 1
1 2 3 5 6 9 10 15 18 30 45