This question has two parts. First, answer Part A. Then, answer Part B.
Part A
A commercial airliner is cruising at an altitude of 6.5 miles when it begins its descent. At the same time a private jet is cruising at an altitude of
8 miles and begins its descent to land. The equation y=x+6.5 represents the altitude of the airliner y, in miles, x minutes after
beginning to descend. The equation y -x+8 represents the altitude of the private jet y, in miles, after x minutes.
Part A
Graph both equations on the coordinate plane to determine which aircraft is flying at a lower altitude after 8 minutes.
Line
Clear
Undo
Altitude (miles)
10-
9
8-
7
6
5
4
3-
2
+
0
4
5
6
7
Time (minutes)
Part B
Which aircraft is flying at a lower altitude after 8 minutes?