Answer :
The ground speed of the plane is 402 mph
We have given,
A plane leaves an airport traveling at 400 mph in the direction n 45° e. a wind is blowing at 40 mph in the direction n 45° w.
Now, Draw a right triangle with 400 and 40 as the two legs.
This is a right angle because 45 degrees NE is perpendicular to 45 degrees NW.
So, the two side lengths are 400 and 40
Using the Pythagorean theorem,
What is the Pythagorean theorem?
(a^2 + b^2 = c^2)
[tex]400^2+40^2=c^2\\\\c^2=160000+1600\\c^2=161600\\c=401.99[/tex]
Therefore the answer is 401.995, or 402mph.
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