Avia is going for a hike over the weekend. She is trying to calculate the distance of traveling one way, and she determines that the trail heads north for 10.4 miles, and then east for another Nine and two-tenths miles. Which distance is the most reasonable estimate for Avia’s one-way hike?

17.5 miles
18.0 miles
19.5 miles
21.0 miles

Which is the equation of an ellipse with directrices at x = ±4 and foci at (2, 0) and (−2, 0)?

Ascientist wants to use a model to present the results of his detailed scientific investigation. why would a model be useful? a )because the model makes the concepts easier to understand b) because the model is easy to put together and to use c) because the model prevents other scientists from asking questions d) because the model requires the audience to pay full attention to it i don't know what to choose because between a and d a is much more likely than d because it only wants to get the attention of the audience. i'm confuse.

These tables represent a quadratic function with a vertex at (0, -1). what is the average rate of change for the interval from x = 9 to x = 10?