Question

Ashley is keeping track of the growth of a bamboo plant. When she purchased the plant last month its height was 8.75 inches. Its height today is 9.5 inches. Assuming that the growth rate remains unchanged, which equation models the height of the bamboo plant after x months of growth? Using the graph, estimate the height of the plant in 6 months. A) y = .75x; about 11 inches B) y = x + 9.5; about 15 inches C) y = 8.75x; about 52.5 inches D) y = .75x + 8.75; about 13.25 inches

Answer 1

D) y = .75x + 8.75; about 13.25 inches

Explanation:

The y-intercept is the starting point. According to the graph, the equation started at a y-intercept that is under 9 but above 8. That cancels choices A and C because there is no y-interecpt in the equation. B is then cancels because the y-intercept is above 9 when the graph clearly shows that it is below 9. The only answer choice left is D.

Answer 2

The answer is D. It grows .75 inches each month and is already 8.75 inches from the start.