Question

David and Amy start at the same point and begin biking in different directions. David is biking west at a speed of 17 miles per hour. Amy is biking south at a speed of 15 miles per hour.

Answer 1

Answer: 1.01 hours. THIS IS CORRECT

SteIf you draw a figure to model the situation, you can think of them as starting at the origin (0,0). After t hours, David will be at the point (−17t,0), and Amy will be at the point (0,−15t):

A line segment on a coordinate plane.

A coordinate plane has an unlabeled horizontal x-axis and an unlabeled vertical y-axis. A line segment labeled D that falls from left to right extends from a solid circle at left-parenthesis negative 17 t comma 0 right-parenthesis to a solid circle at left-parenthesis 0 comma negative 15 t right-parenthesis. A point is plotted at left-parenthesis 0 comma 0 right-parenthesis. All plotted points are labeled with their coordinates.

Using the distance formula, we can find the distance between them as a function of time t:

D(t)=(x0−x1)2+(y0−y1)2‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾√=(−17t−0)2+(0−−15t)2‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾‾√=289t2+225t2‾‾‾‾‾‾‾‾‾‾‾‾‾√=514t2‾‾‾‾‾√=t514‾‾‾‾√

(Note that we can say t2‾‾√=t and not |t| because in this question t>0). Setting this equal to 23 and solving for t, we find

t514‾‾‾‾√t=23=23514‾‾‾‾√≈1.01p-by-step explanation:

Answer 2

What is the question you only gave the info