Find the slope of the line through the given points. (3,4) and (8,-3)

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 .

Simplify. 3(4+4x) (type your answer in with no spaces)

What is the inverse of f(x) = 6x -24