![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/step1.JPG\")
Factor the each monomial.
\18c = 2 · 3 · 3 · c
\4c = 2 · 2 · c
\The GCF is the product of the common prime factors in each monomial.
\The common prime factors are 2 and c.
\The GCF is 2 · c = 2c.
\The greatest common factor of 18c and 4c is 2c.![\"\"](\"http://www.mathskey.com/userfiles/image/steps_images/solution.JPG\")
The greatest common factor of 18c and 4c is 2c.