SOLUTION: Convert to polar: {{{y=4}}} A.) {{{r=4}}}/cosΘ B.) {{{r=4}}}cosΘ C.) {{{r=4}}}sinΘ D.) {{{r=4}}}/sinΘ

Algebra ->  Trigonometry-basics -> SOLUTION: Convert to polar: {{{y=4}}} A.) {{{r=4}}}/cosΘ B.) {{{r=4}}}cosΘ C.) {{{r=4}}}sinΘ D.) {{{r=4}}}/sinΘ      Log On


   

Question 1079795: Convert to polar: y=4
A.) r=4/cosΘ
B.) r=4cosΘ
C.) r=4sinΘ
D.) r=4/sinΘ
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
These are two equations you should have in your notes, on a notecard, or some reference sheet.

Ideally you should memorize them

x+=+r%2Acos%28theta%29
y+=+r%2Asin%28theta%29

We will use the second equation.

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y+=+r%2Asin%28theta%29 Start with the equation mentioned above

4+=+r%2Asin%28theta%29 Plug in y = 4

r%2Asin%28theta%29+=+4 Flip the equation

%28r%2Asin%28theta%29%29%2F%28sin%28theta%29%29+=+4%2F%28sin%28theta%29%29 Divide both sides by sin(theta)

r+=+4%2F%28sin%28theta%29%29 Simplify (note: sin(theta) can't be equal to 0)

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The final answer is choice D