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Algebra 1

4.5.5 Using Graphical and Algebraic Approaches for Finding Unknowns of Linear Functions

Algebra 14.5.5 Using Graphical and Algebraic Approaches for Finding Unknowns of Linear Functions

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The college student who is looking for a data plan for her cell phone found a third option, which also offers a 2-gigabyte monthly allowance for data.

The monthly cost of this option can be represented by function CC, defined by C(x)=30x+5C(x)=30x+5, where xx is the gigabytes of data used over the monthly allowance.

1.

Find C(0.7)C(0.7) and explain what it means in this situation.

2.

Her budget is still $50 a month. To find out how many gigabytes of data she could use if she chose this plan, she writes C(x)=50C(x)=50 and solves for xx. What value of xx makes this equation true? Be prepared to show your reasoning.

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