Problema Solution

A 2-mi cab ride costs $5.25. A 5-mi cab ride costs $10.50.Which equation models the cost y of the cab ride for a ride that is x miles?

Answer provided by our tutors

We will solve assuming the equation that models the cost is linear. 

y = mx + b, where 'm' is the slope, 'b' is the y - intercept

We are given two point of the line (2, 5.25) and (5, 10.50).

m = (10.50 - 5.25)/(5 - 2)

m = 7/4

y = (7/4)x + b

Plug x = 2, y = 5.25 to find b:

(7/4)*2 + b = 5.25

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click here to see the equation solved for b

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b = 7/4

The linear equation that models the cost is:

y = (7/4)x + 7/4