A tennis ball dipped in red paint rolls around on the coordinate plane, so that it is at
(x,y) = (t,2t) at time t, where 0 <= t <= 4. Find the length of the paint trail left by the tennis ball.
At t= 0 it is at 0,0
at t= 4 it is at 4,8
use distance formula or pytheg theorem to find d
d2 = 42 + 82 ........finish.....
