Question

The graph below shows the price, y, in dollars, of different amounts of peanuts, x, in pounds:

A graph titled Peanut Prices shows Number of Pounds on x axis and Price in dollars on y axis. The scale on the x axis shows numbers from 0 to 12 at increments of 2, and the scale on the y axis shows numbers from 0 to 36 at increments of 6. A straight line joins the ordered pairs 0, 0 and 12, 36.
Which equation best represents the relationship between x and y? (5 points)

y = 6x
y = x + 6
y = 3x
y = x + 3

Answer 1

Since the line goes through (0, 0), it can be described by

y = kx

You are given the point (12, 72), so you know

72 = 12k

6 = k . . . . . . . divide by 12

Then the equation of the line is ...

y = 6x