Use repeated sustraction or a number line to solve

You and a friend race across a field to a fence and back. your friend has a 50-meter head start. the equations shown represent you and your friend's distances dd (in meters) from the fence tt seconds after the race begins. find the time at which you catch up to your friend. you: d=∣−5t+100∣d=∣−5t+100∣ your friend: d=∣−313t+50∣∣

Icould really use some with this question.

Acompany made a profit of 75000 over a period of 6 years on an initial investment of 15000 what is the annual roi