My car gets 23 miles per gallon at 60 miles per hour. Is the number of miles I can drive at 60 miles per hour a linear function of the number of gallons of gas in the tank? Explain your reasoning.

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  yes

Step-by-step explanation:

The constant ratio (23 mi)/(1 gal) tells you the number of miles is a linear function of the number of gallons.

  miles = (miles/gallon) × gallons

  miles = constant × gallons . . . . . a linear function of gallons

step-by-step explanation:

first, eliminate the parenthesis:

3

x

+

2

−

4

x

second, group like terms:

3

x

−

4

x

+

2

third, combine like terms:

(

3

−

4

)

x

+

2

→

−

1

x

+

2

→

−

x

+

2