# Expressing polar equation as a Cartesian equation

## Homework Statement

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

## Homework Equations

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

## The Attempt at a Solution

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

BiP

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## Homework Statement

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

## Homework Equations

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

## The Attempt at a Solution

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

BiP

## The Attempt at a Solution

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

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

Thanks!

BiP