Question

A 3-mi cab ride costs $3.00. A 6-mi cab ride costs $4.80. Find a linear equation that models cost c as a function of distance d. c = 1.00d + 1.80 d = 0.60c + 1.80 c = 0.60d + 1.20 c = 0.80d + 1.20

Answer 1

D. c = 0.60d + 1.20

Explanation:

Answer 2

c=0.6d+1.2

Explanation:

Let c the cost and d the distance. The linear equation has the form

c=md+b

the slope m can be computed by means of the given points:

(d1,c1)=(3,3)

(d2,c2)=(6,4.8)

where

`m=(c2-c1)/(d2-d1)`

hence

`m=(4.8-3)/(6-3)\\m=(1.8)/(3)\\m=0.6`

Now, we must find the y-intercept "b" in the equation c=0.6d+b, by using the point (3,3), that is

3=0.6(3)+b

3=1.8+b

b=3-1.8

b=1.2

Finally, the answer is

c=0.6d+1.2