# Expressing polar equation as a Cartesian equation

1. Sep 22, 2012

### Bipolarity

1. The problem statement, all variables and given/known data

Express the following equation in Cartesian form
$$r = 1 - cos(θ)$$

2. Relevant equations
$$x = r*cos(θ)$$
$$y = r*sin(θ)$$
$$r^{2} = x^{2} + y^{2}$$
$$tan(θ) = \frac{y}{x}$$

3. The attempt at a solution

I have no idea... a hint would be nice thanks!

BiP
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Sep 22, 2012

### gabbagabbahey

If $x=r\cos\theta$, what is $\cos\theta$? If $x^2+y^2=r^2$, and $r\geq 0$, what is $r$?

3. Sep 22, 2012

Thanks!

BiP