Factor the expression 20K+50 and explain how.

The greatest common factor of 20k (20 times k) and 50 is 10. So factor out a ten from both.

10 (2k+5)

We are given with two terms: 20 k and 50. In this case, we are asked in the problem to factor the two terms forming the expression. The common factor of 20k and 50 is 10 because the two terms are divisible by it. The answer hence is 10 * (2k + 5)