Question

Which equation best represents c, the total amount Mr. Thomas should be charged

for driving m miles?

Answer 1

c = 0.15m + 45

Explanation:

Generally, we have the equation of a straight line as;

y = mx + b

where m is the slope and b is the y-intercept

To get the value of m, we can use the slope equation

m = (y2-y1)/(x2-x1)

Let us select two points to use from the table

we have;

(40,51) and (20,48)

So substituting these values;

m = (48-51)/(20-40) = 0.15

So we have the partially completed equation as;

y = 0.15x + b

To get the value of b, we use any of the points

Using the last, we have

51 = 0.15(40) + b

b = 45

So we have the complete equation as;

y = 0.15x + 45

using the terms in the question, we have;

c = 0.15m + 45