"in how many ways can we make a list of three integers"

Iam trying to solve a linear equation for the shoe size of someone 84" tall taking into consideration example 1 is 69" tall with a shoe size of 9 and example 2 is 72 inches tall with a shoe size of 11. i understand that the equation should be y=mx+b and that on the graph the answer is (3,2) but i just don't understand how to create the equation to solve for 84-inches and 60-inches tall questions. after two days, i need .

Factor the polynomial by its greatest common monomial factor.

Evan walked 5/8 mile to his friends house. then together they walked 7/12 mile to the movie theatre. which pair of fraction can evan use to find how far he walked in all?