Question

How do you convert `x^2 + y^2 = 4x` into polar form?

Answer 1

It is `r=4*cos(theta)`

Explanation:

We can rewrite this using the following transformation

`x=r*cos(theta)` and `y=r*cos(theta)`

so we have that

`r^2*cos^2(theta)+r^2*sin(theta)-4r*cos(theta)=0=> r*[r*cos^2(theta)+r*sin^2(theta)-4*cos(theta)]=0=> [r*(cos^2(theta)+sin^2(theta))-4cos(theta)]=0=> r=4cos(theta)`