Question

The scatterplot shows the distance (in feet) that a person was from a motion sensor during an experiment in math class. Use the labeled points to create a linear model. About what distance in feet (y) would a person be 8 seconds after the experiment begins?

mc008-1.jpg
21 ft
27 ft
30 ft
57 ft

Answer 1

I can’t see the image here — could you either upload it or tell me the coordinates of the two labeled points on the plot? I’ll use those to make the linear model and compute y at t = 8 s.

How I’ll do it (quick steps):
1. Take two labeled points (x1,y1) and (x2,y2).
2. Slope m = (y2 − y1) / (x2 − x1).
3. Find intercept b from y1 = m x1 + b (so b = y1 − m x1).
4. Linear model y = m x + b. Evaluate y at x = 8.

Example: if the points were (0, 6) and (4, 18), then m = (18−6)/(4−0)=3, b = 6, so y = 3x+6 and y(8) = 3(8)+6 = 30 ft.

Send the image or the two point coordinates and I’ll compute the exact answer.