Note how we can distribute the 10 back in to check our work 10(2k+5) = 10(2k)+10(5) = 20k+50 so that confirms we have the right answer
Another thing to notice is that 10 is the largest factor that we can pull out of 20k and 50. The value 10 is the GCF (greatest common factor) of 20 and 50.
