Question

How do you convert `x+2y-4=0` into a polar equation?

Answer 1

Use the following identities ...

`x=rcostheta`
`y=rsintheta`

Explanation:

Using the above identities, substitute into the original equation ...

`rcostheta+2rsintheta=4`

Next, solve for r ...

`r=4/(costheta+2sintheta`

hope that helped