# Lesson 1

Understanding Proportional Relationships

Let’s study some graphs.

### Problem 1

Priya jogs at a constant speed. The relationship between her distance and time is shown on the graph. Diego bikes at a constant speed twice as fast as Priya. Sketch a graph showing the relationship between Diego’s distance and time.

### Problem 2

A you-pick blueberry farm offers 6 lbs of blueberries for \$16.50.

Sketch a graph of the relationship between cost and pounds of blueberries.

### Problem 3

A line contains the points $$(\text-4,1)$$ and $$(4,6)$$. Decide whether or not each of these points is also on the line:

1. $$(0,3.5)$$
2. $$(12,11)$$
3. $$(80,50)$$
4. $$(\text-1,2.875)$$
(From Unit 2, Lesson 12.)

### Problem 4

The points $$(2,\text-4)$$, $$(x,y)$$, $$A$$, and $$B$$ all lie on the line. Find an equation relating $$x$$ and $$y$$.

(From Unit 2, Lesson 11.)