SOLUTION: Write the rectangular form of the polar equation r-3 sin theta=0

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Question 983185: Write the rectangular form of the polar equation r-3 sin theta=0
Answer by Edwin McCravy(20064) About Me  (Show Source):
You can put this solution on YOUR website!
I won't do yours for you.  I'll do one exactly like it instead
and you can use it as a model to do yours by.  I'll do this
one instead which uses cosine instead of sine:

r-4cos%28theta%29%22%22=%22%220

Always draw this picture when converting from polar to ractangular 
or from rectangular to polar::



Looking at the triangle in the picture above you can see these:

y%2Fr=sin%28theta%29, x%2Fr=cos%28theta%29, r%5E2=x%5E2%2By%5E2

Then solve for y, x and r

y=r%2Asin%28theta%29, x=r%2Acos%28theta%29,  {r=sqrt(x^2+y^2)}}}

ALWAYS WAIT TILL LAST TO SUBSTITUTE FOR r. Substitute for x and y
first. Then simplify.

r-4cos%28theta%29%22%22=%22%220

r-4%28x%2Fr%29%22%22=%22%220

Multiply through by r

r%5E2-4x%22%22=%22%220

NOW, FINALLY, we substitute for r2.

x%5E2%2By%5E2-4x%22%22=%22%220   <-- answer

That's it!.

Now do yours the same way, only use the sine instead.

Edwin