A space traveler is moving from left to right along the curve $$y=x^2.$$ When she shuts off the engines, she will continue traveling along the tangent line at the point where she is at that time. At what point
$(x,y)= ($ , $)$
should she shut off the engines in order to reach the point $(4,15)$?
If she was traveling from right to left she would have to shut off the engines at the point $(x,y)= ($ , $)$.