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Systems of Equations in the Real-World

2.2.4 Systems of Equations in the Real-World

2.2.4 • Systems of Equations in the Real-World

Cool Down

Translate to a system of equations and then solve:

When Jenna spent 10 minutes on the elliptical trainer and then lifted weights for 20 minutes, her fitness app said she burned 278 calories. When she spent 20 minutes on the elliptical trainer and 30 minutes lifting weights she burned 473 calories. How many calories does she burn for each minute on the elliptical trainer? How many calories does she burn for each minute of lifting weights?

Let x=x= calories burned per minute on the elliptical and y=y= calories burned per minute lifting weights.

1.

Write a system of equations.

Compare your answer:

10x+20y=27810x+20y=278

20x+30y=47320x+30y=473

2.

Use the graphing tool or technology outside the course. Graph the equation that represents this scenario using the Desmos tool below.

Access multimedia content

Compare your answer:

A graph with two descending lines: a solid orange line and a dashed blue line, both sloping downward from left to right over a grid with labeled axes. The orange line is above the dashed blue line.
3.

Use the graph to estimate the solution.

Compare your answer:

Answers may vary. Here is a sample response.

(11,8.5)(11,8.5)

The elliptical burns about 11 calories per minute. Lifting weights burns about 8.5 calories per minute.