Question

How do you write the equation `6x-8y=21` in polar form?

Answer 1

`r=21/(2(3costheta-4sintheta))`

Explanation:

To convert from `color(blue)"cartesian to polar form"`

`color(orange)"Reminder " color(red)(bar(ul(|color(white)(2/2)color(black)(x=rcostheta , y=rsintheta)color(white)(2/2)|)))`

substitute into the equation.

`rArr6(rcostheta)-8(rsintheta)=21`

`rArr2r(3costheta-4sintheta)=21`

`rArrr=21/(2(3costheta-4sintheta))`