For two readings from a linear model, the slope is the steady change in output for each one-unit increase in input. Divide altitude change by elapsed time to get meters per second. Put the readings into a slope fraction and let Desmos evaluate it. The total rise alone is not a per-second rate; check the sign against whether the altitude rises or falls.
Hints
- Hint 1
A point on this graph pairs a time with an altitude. Time is the input, so write seconds first and meters second. What two points do the readings give?
- Hint 2
The slope compares the change in altitude with the change in time. Subtract in the same order for both changes. As time moves forward, does the altitude rise or fall?
Step-by-step
Find and interpret the slope from two readings
Step 1Read the points and check the direction
A point pairs time with altitude, so the readings give and . Time and altitude both rise from the first point to the second, so the slope is positive, not a decrease.
- Step 2
Calculate the per-second rate
The slope is altitude change divided by time change. Type in Desmos, using later minus earlier in both places. Desmos shows . Altitude is measured in meters and time in seconds, so the drone’s altitude increases by meters per second. Choice D.