Hello I need clarifications for this.

"An airplane capable of an airspeed of 100 km/hr is 60 km off the coast above the sea. If the wind is blowing from the coast out to sea at 40 km/hr, what is the least amount of time it will take for the plane to get to shore?"

With the image below why cant we use pythagoreon theorem to find the velocity of the groundspeed and then use the equation t=d/v? I tried it and it did not give the correct answer. However, finding the groundspeed would be the velocity of the airplane with the wind, so I am unsure why it does not work.

I do not want the answer I already know it, I just want to know why my calculations are not working (100^2+40^2=groundspeed^2)

Drill CHAPTER 3 PRACTICE PASSAGE An airplane is susceptible to substantial deflection off course due to wind. A pilot calls the engines' contribution the airspeed. This motion relative to the air, combined with the wind velocity, results in the ground speed, or velocity relative to fixed terrestrial objects. wind ei airspeed ground speed 19600-10600= 1780 - 10 10. 10 - 100 gramerpued 091 60 Figure 1adsare no18 1780 = 10 10. 10 - 100 0=/ 60 grandiped Figure 1 When a parachutist typically leaves an airplane, it is not so much a jump as a drop. He steps out of a door or lets go of a strut under the wing, not giving him any significant velocity relative to the airplane. He becomes subject to gravity without the lift of the wings. Air resistance allows the plane to get ahead of him. If we neglect this drag effect, then the parachutist's constant horizontal velocity and constant vertical acceleration gives him a trajectory resembling half of an inverted parabola. This is a reasonable assumption for the free fall before the parachute is engaged. 10.54 68 | For More Free Content, visit PrincetonReview.com