Unit 2 Ratio and Proportional Relationships Lesson 5A Graphing 7.RP.2/ MP: 1-4

Do Now

• There are 9 red gumdrops, 10 yellow gumdrops, and 15 orange gumdrops in a bag. What is the ratio of orange gumdrops to red gumdrops in the bag?

• • 5 20 a true proportion?

12 x

Let’s Go Over Homework Answers WB Pg 11 #20-27

DO NOW

1. There are 9 red marbles, 5 yellow marbles, and 12 blue marbles in a bag. What is the ratio of blue marbles to red marbles in the bag?

2. Is 4 16 5 20 a true proportion?

3. Solve for x: 6 = 8 12 x

Objective:

• Students will graph relationships on a coordinate plane and determine if a relationship is proportional.

Review: Graphing on a Coordinate Plane

Quadrant II

y

Quadrant I

X: move right 2 units

(

2

,

3

)

Y: move up 3 units ( 2 , 3 ) ( 0 , 0 )

(x, y)

origin

Quadrant III Quadrant IV

Helpful Hint The sign of a number indicates which direction to move. Positive: up or right Negative: down or left

x

• • Ms. Umstetter is planning a year-end pizza party for her students.

Cascarino’s Pizza is offering free delivery and charges $8 per medium pizza.

• 1) complete the table to determine the cost for different numbers of pizzas ordered.

• • Pizza Cost ($) 1 8 16 • • • • 2) Write the relationship of the cost and number of pizzas as a ratio in simplest form 3) What do you notice about the simplified ratios?

4) Graph the chart on a coordinate plane and connect the points. Describe the graph. 5) Is the relationship proportional?

Graph

Notes

• Another way to determine whether two quantities are proportional is to graph the quantities on the coordinate plane.

• If the graph of the two quantities is a straight line through the origin , then the two quantities are proportional.

• CW: WB pg 17 • HW: Rates & Ratios 2 Wksht