Question 5 Problems 5 – 6: You ride your bike and measure how far you travel. After 10 minutes you travel 2.5 miles. After 30 minutes, you travel 7.5 miles. Write an equation to model your distance.

Answer 1

model using equation of line of form y = mx + b where m is slope and b is y intercept.

let x = time in minutes; y = distance in miles

x y

10 2.5

30 7.5

compute slope as change in y (5)/ change in x (20) = 1/4

so now we have y = 1/4 x + b

substitute x and y = 10 and 2.5 to solve for b:

2.5 = 1/4(10) + b

b = 0

so equation is y = 1/4x = x/4

miles = minutes/4