What is the quarter circle's radius?

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 .

Atriangle with all sides of equal length is a/an triangle. a. right b. scalene c. equilateral d. isosceles

Find each value of the five-number summary for this set of data. [note: type your answers as numbers. do not round.] 46, 19, 38, 27, 12, 38, 51 minimum maximum median upper quartile lower quartile