Algebraic Substitution

Question

A hawk takes off from the ground ascending 80 feet per minute. At the same time an eagle is flying at 1200 feet and descending 70 feet per minute. After how many minutes will the 2 birds be at the same altitude? What is the altitude birds?

Answer 1

Let x = number of minutes flown by each bird

Height of hawk in x minutes = 80x

Height of eagle in x minutes = 1200 - 70x

The birds are at the same altitude when 1200 - 70x = 80x

150x = 1200

x = 8 minutes

The birds will be at the same altitude after 8 minutes. At that time, each bird will be 640 feet above the ground.