Find the factors prime or composite 21

Hello There! :)

21 is composite.

Keep in mind that if we can take a number and add its digits and get 3, 6, or 9, then the number is composite.

The factors of 21 are: 1. 3, 7, 21

Hope it helps! :)

step-by-step explanation:

given that there are two triangles j'k'l' and jkl>

the former is got by dilating the second one.

when drawn on a grid, (graph paper) coordinates of vertices of first triangle is

(6,12)j, (9,6)k and (12,9)l

side jk has length = distance between j and k

=

side j'k'=distance between j' and k'

=

ie j'k'l' has sides 1/3 of that of corresponding sides of jkl.

hence scale factor of 1/3 is used to get j'k'l'from jkl