Vector magnitude and direction question

AI Thread Summary
Vector C is determined by the components of vectors A and B, yielding x = 1 and y = -3. The magnitude of vector C is calculated to be 3.2. The direction is causing confusion, as the calculated angle of -72 degrees is deemed incorrect by the online problem checker. Suggestions include expressing the angle in a standard format, possibly between 0 and 360 degrees, or using cardinal directions like "East 72 South." Clarifying these details may resolve the issue with the direction answer.
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Homework Statement



Suppose vector C = vector A + vector B where vector A has components vector A x = 4, vector A y = 2 and vector B has components vector B x = -3, vector B y = -5.
(a) What are the x- and y- components of vector C ?

I've solved this to figure out that x = 1 and y = -3 for C

(b)What are the magnitude and direction of vector C ?
magnitude I've solved this to be 3.2
direction ? (clockwise from the x-axis) This is what I can't get. I've solved for the angle and gotten -72 degrees using tan -3/1. Does anybody know what I'm doing wrong?

Homework Equations


The Attempt at a Solution

 
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Why do you say that answer is wrong. Perhaps you are not being accurate enough. 71 degrees, 35 minutes is slightly more accurate, 71 degrees, 34 minutes, and 36 seconds even more accurate. Or perhaps they want the answer in radians.
 
It's an online problem that checks itself when you put in the answer. It's telling me that my answer of -72 degrees is wrong and I'm not sure why. Also, it wants it in degrees specifically.
 
I've solved this to figure out that x = 1 and y = -3 for C

If X is 1 then that would be east, and given that the Y component is negative, its south.

I don't know the details of the question, but try East 72 South
 
Perhaps they want an answer between 0 and 360 degrees.
 
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