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