Two Related Quantities, Part 1

Warmup

Activity #1

Graphing two related Quantities.

In the following activity, you are going to complete the table below of two related quantities and draw the graph.

Lin needs to mix a specific shade of orange paint for the set of the school play. The color uses 3 parts yellow for every 2 parts red.

• Complete the table to show different combinations of red and yellow paint that will make the shade of orange Lin needs.

Lin notices that the number of cups of red paint is always  of the total number of cups. She writes the equation  to describe the relationship.

(1.) Which is the independent variable? Which is the dependent variable? Explain how you know.

(2.) Write an equation that describes the relationship between r and y where y is the independent variable.

(3.) Write an equation that describes the relationship between y and r where r is the independent variable.

In this next activity, you are going to use the points in the table above to create a graph that shows the relationship between r and y.

• Match each relationship to one of the equations you wrote in (2) and (3) above.

In this next activity, you are going to use the points in the table to create a graph that shows the relationship between r and y.

• Match each relationship to one of the equations you wrote in (2) and (3) above.

Activity #2

Graphing two Related Quantities.

In the following activity, you are going to complete a table of two related quantities, and then transfer the data to a coordinate plane.

• Read the following story, and then complete the table to show how much Kiran pays for books during the sale.

Kiran shops for books during a 20% off sale. What percent of the original price of a book does Kiran pay during the sale?

• Create a graph below showing the relationship between the sale price and the original price by plotting the points from the table.

Activity #3

Complete a Table of Coordinate Pairs.

In the activity below, you are going to examine a graph that shows some values for the number of cups of sugar,  required to make  batches of brownies.

• Study the graph carefully and complete the table so that the pair of numbers in each column represents the coordinates of a point on the graph..

(1.) What does the point (8, 4) mean in terms of the amount of sugar and number of batches of brownies?

(2.) Write an equation that shows the amount of sugar in terms of the number of batches.

Challenge #1

Evaluate the expression when is 4 and is 6.

Challenge #2

Evaluate the expression when is 4 and is 6.

Challenge #3

Evaluate the expression when is 4 and is 6.