Angles of a Vector on the Coordinate Plane

AI Thread Summary
The discussion revolves around identifying angles equivalent to 18 degrees below the -x-axis in a physics homework problem. The user initially selected option A but later expressed confusion about their choices and sought clarification on the correct answers. They considered changing their selections based on their reasoning but were unsure. Ultimately, the user realized their mistake and felt relieved after figuring it out. The conversation highlights the importance of visualizing angles on a coordinate plane for better understanding.
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Homework Statement



This question is on my physics homework, I guess it could be posted elsewhere, but I'm not sure where. Here is the problem:

Which of the following are the same as 18 degrees below the -x-axis? Choose all that apply:

!The choices I selected are in red!

A) 72 degrees left of the -y-axis
B) 72 degrees right of the +y-axis
C) 18 degrees right of the +y-axis
D) 72 degrees below the -x-axis
E) 18 degrees above the +x-axis
F) 72 degrees above the +x-axis
G) 18 degrees left of the -y-axis

Homework Equations


None

The Attempt at a Solution


I got the answer wrong. I chose choice A. because I subtracted 90 degrees (-y-axis) from 18 giving me 72.

I am thinking that I should change choice B. to C.and choice E. to F.? However, honestly I'm confused with my reasoning behind this. Nothing in my text speaks on this. Can anyone help? Thanks for your time.

Also, if my question would be best answered in another place, please let me know. Like I said, this is from my physics homework...
 
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This seems quite simple.

Try Drawing a graph to illustrate what it may look like.

Then try to see which fits the descriptions best.

I think http://www.studentforums.biz/index.php site, will be able to give you a quicker reply, as they specialize in homework
 
Last edited by a moderator:
Oooops I figured it out and I feel really silly lol.

Thanks for the reply anways!
 
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