30*60 = 1800 seconds
* 4 m/s = 4*1800 meters
2 pi r = 200 pi meters circumference
4 *1800/200 pi = 36/pi= 11.459 circles
= 11 circles + .459 circle
.459 * 360 = 165 degrees
x = 100 cos 165 = -96.6
y = 100 sin 165 = +25.9
Lisa is running around the circular track x^2+y^2=10000, whose radius is 100 meters, at 4 meters per second. She starts at point (100,0) and runs in the counterclockwise direction. After 30 minutes of running, what are her coordinates?
1 answer