When are x2+2x/5x and it's simplified form equal

Find an equation of the line perpendicular to the graph.

You are at a restaurant and owe $56.20 for your meal. you want to leave an 18% tip. approximately how much is your tip?

This size running track is usually called a 400 meter track. however if a person ran as close to the inside as possible on the track they would run less than 400 meters in one lap. how far away from the inside border would someone have to run to make one lap equal exactly 400 meters