Alright, here's the problem I need help with:(adsbygoogle = window.adsbygoogle || []).push({});

A watermelon seed has the following coordinates: x = -7.2 m, y = 1.4 m, and z = 0 m. Find its position vector as (a) a magnitude and (b) an angle relative to the positive direction of the x axis. If the seed is moved to the xyz coordinates (5.9 m, 0 m, 0 m), what is its displacement as (c) a magnitude and (d) an angle relative to the positive direction of the x axis?

Parts a through c I've solved and have correct, but my answer to d is being rejected. I don't understand why.

For a I got 7.3m.

For b I got 169 degrees.

For c I got 13.2m.

However, for d I get 174 degrees, but that's wrong. I used the same proceedure for part b and got that right though! Could someone explain why please?

Thanks in advance!

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# Homework Help: Why is this incorrect? (Two-dimensional motion problem)

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