## emersonba123 2 years ago Determine two pairs of polar coordinates for the point (4,-4) with 0° ≤ θ < 360°

1. FutureMathProfessor

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2. FutureMathProfessor

So the radius (r coordinate) is sqrt(32) and the first theta coordinate is 315 degrees. add another 360 to that to get a second theta coordinate, with r constant at sqrt(32)

3. emersonba123

You got the sqrt of 32 because r=x^2+y^2. Since it is in the fourth quadrant that's why it is 315 degrees? The answer has to be between 0 and 360 degrees

4. emersonba123

I'm not sure how you got 315 degrees

5. myininaya

@FutureMathProfessor Theta has to be between 0 and 360 degrees so that means there will be one r being positive and one r being negative in another pair of coordinates.

6. myininaya

One pair you found (sqrt(32),315) The other one will have a negative r.

7. emersonba123

(4 , 315°), (-4 , 135°) is this the answer?

8. emersonba123

it shoud say 4sqrt2

9. myininaya

you can simplify sqrt(32) I'm sure. :) But yes.

10. emersonba123

Thank you very much!

11. myininaya

But your r's are wrong and those pairs you gave.

12. myininaya

Oh wait are you saying 4 or 4sqrt2?

13. emersonba123

4sqrt2 in the coordinate for the r