Independent and Dependent Variables

An equation with two variables shows a relationship between two quantities. The value of the dependent variable changes according to the value of the independent variable.

1. Kenneth earns $9 per hour mowing lawns. The total amount earned y equals the amount earned per hour times the number of hours x.

A) What is the independent variable and what does it stand for in the problem? ______

B) What is the dependent variable and what does it stand for in the problem? ______

C) Write an equation to find the amount of money Kenneth would make mowing lawns.

______

D) Using your equation fill in the chart below. E) Graph your chart.

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2. Maria earns $45 for every lawn that she mows. Her earnings y in dollars depend on the number of lawns x that she mows.

A) What is the independent variable and what does it stand for in the problem? ______

B) What is the dependent variable and what does it stand for in the problem? ______

C) Write an equation to find the amount of money Maria would make mowing lawns.

______

D) Using your equation fill in the chart below. E) Graph your chart.

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3) Neema purchases a gallon of milk for $3 and some tomatoes for $2 per pound from the grocery store. Let y be the total amount Neema spends at the store and x is the weight of the tomatoes.

A) What is the independent variable and what does it stand for in the problem? ______

B) What is the dependent variable and what does it stand for in the problem? ______

C) Write an equation to find the amount of money Neema will spend at the grocery store.

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D) Using your equation fill in the chart below. E) Graph your chart.

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4) Hakeem wants to rent a bike. Bike rental costs $5 per hour plus a one-time service fee of $3 for renting the bike. Let x stand for the number of hours Hakeem has the bike and y stand for the total charge.

A) What is the independent variable and what does it stand for in the problem? ______

B) What is the dependent variable and what does it stand for in the problem? ______

C) Write an equation to find the amount of money Hakeem will spend to rent a bike.

______

D) Using your equation fill in the chart below. E) Graph your chart.

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