TRIGONOMETRY
posted by Kate on .
Can you please help me with this question on my study guide for my trig final? Thanks! I'd also appreciate if you can check out my other postings and check my work for some other study guide questions. I want to make sure I'm ready for my final. :)
4. Transform each polar equation to an equation in rectangular coordinates and identify its shape.
a. r = 6
b. r = 2cosθ
Answer:

r=6 is just a circle of radius 6
x^2+y^2 = r^2
This is also a circle, but shifted along the xaxis:
r = 2cosθ
r^2 = 2rcosθ
x^2+y^2 = 2x
x^22x+1 + y^2 = 1
(x1)^2 + y^2 = 1