Find a Cartesian equation for the curve. r cos ? = 7.

Question

I have been trying at my wits end to understand how to approach this problem but I cannot seem to get a correct answer. I think I need to start from scratch with some advice. Thank you!

Answer 1

x = r cos θ

y = r sin θ

 

x = r cos ? = 7

x = 7

Answer 2

If you meant to type, rcosΘ= 7,

 

x= rcosΘ, so this is the equation of a vertical line:

 

x= 7

 

- Ben