What are all the greatest common factors of 36 and 90?

##GCF = 18## Common factors:## " " 1 , 2, 3, 6, 9, 18##

There can be several common factors, but there is only one .

Write 36 and 90 as the product of their prime factors.

##36 = 2xx2xx3xx3##

##90= color(white)(xxx)2xx3xx3xx5##

##GCF =color(white)(x)2xx3xx3 color(white)(xxx) =18##

As for all the common factors, it is probably easiest to write all the factors of 36 and then select which are factors of 90 as well.

Factors of 36: ##" "1, 2, 3, 4, 6, 9, 12, 18, 36## Common factors:##" "1, 2, 3, 6, 9, 18##