Trigonometry

Oh ok. So I’m in grade 11, math 20-1. Unit trigonometry. So for “a” I found that r= √13. Sin= 3/√13, cos= -4/√13, tan = 3/-4. But the answers say 2/√13, -3/√13, and -2/3.
 
I am having a bit of trouble here. It's hard to read that sideways picture.

But as I see problem 9, the terminal point is (-4, 3), which gives me a hypotenuse of 5, not [MATH]\sqrt{13}.[/MATH]
In problem 10, the terminal point is (-2, 3), which does give a hypotenuse of [MATH]\sqrt{13}.[/MATH]
In your original post, you asked about problem 9.

Has trying to look at a picture sideways loosened my brains?

EDIT: Oh, and thank you for reading up on what we expect.
 
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What point are you using to get these numbers? Your r= √13 suggests you're working from some point like (-2, 3); and their answers would fit that even more. But I don't see anything like that in the picture. What I do see is (-4, 3). (I wish they'd made that more obvious by putting a dot there.)

On the other hand, problem 10, which is not the one you said you're asking about, does involve (-2, 3). Are you sure you're looking at the answer to the right problem?
 
Dr.Peterson said:
What point are you using to get these numbers? Your r= √13 suggests you're working from some point like (-2, 3); and their answers would fit that even more. But I don't see anything like that in the picture. What I do see is (-4, 3). (I wish they'd made that more obvious by putting a dot there.)

On the other hand, problem 10, which is not the one you said you're asking about, does involve (-2, 3). Are you sure you're looking at the answer to the right problem?
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Oh well yeah guys, the answers for #9 are similar to #10. I'm just trying to understand the solution for #9
 

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