Speed of plane a = 450 mph.
speed of plane b = 350 mph.
both planes leave from kansas city at the same time.
plane a flies due west.
plane b flies due south.
after 2.5 hours, how far is plane a from plane b?
a. 1,425.0
b. 1,322.0
c. 1,258.5

The answer would be A:

You would use distance=rate•time to solve:

450 • 2.5 = 1125
350• 2.5 = 875

Since plane A is going west and B is going south, they form a right triangle, so you can use the Pythagorean theorem to solve for the distance between them, which we will represent as x:

1125² + 875² = x²
1265625 + 765265 = x²
2030890 = x²

Once you square root x, it's about 1425.09298, which is closest to answer A, 1425.0