How do you find the GCF of #10ab, 25a#?

2 Answers
Aug 11, 2017

#5a#

Explanation:

To find the GCF, look for the factor that both terms have in common
This one is #5a#

Aug 11, 2017

#HCF = 5a#

Explanation:

Write each term as the product of its prime factors:
Identify which factors are common to both

#" "10ab = 2xxcolor(blue)(5)color(white)(xxx)xxcolor(blue)(a)xxb#
#" "25a = ul(color(white)(xx.x)color(blue)(5) xx 5xxcolor(blue)(a))#
#HCF = color(white)(xxxxx)color(blue)(5)color(white)(xxx)xxcolor(blue)(a) = 5a#

This method is very useful if you are working with several numbers, especially of they are large and unfamiliar.