Question

an airplane is at an altitude of 1,200 feet. It begins to ascend at a rate of 925 feet per minute. How many minutes will it take the plane to reach 16,000 feet.

Answer 1

16,000=925x + 1200
You want to find after how many minutes the plane will reach 16000. So you set 16000 as your "y". Your 925 is your slope because that's how much you're increasing by every minute. 1200 is your y int, because that's what you're starting at. 14,800=925x
x=16
16 minutes

Answer 2

You start by subtracting: 16000-1200= 14800
Then you divide 14800 by how many feet the plane rises per minute 
14800/945=16 minutes
The answer is 16 minutes