Write a sine equation for the graph

Which of the following points is collinear with (-2,1) and (0,3)

Two cyclists 84 miles apart start riding toward each other at the samen time. one cycles 2 times as fast as the other. if they meet 4 hours later what is the speed (in miles) of the faster cyclists

Write an algebraic expression to match each statement a. four less than 8 times a number b. twice the difference of a number and six c. nine from a number squared