How do you convert #r=6 cos θ + 4 sin θ# into rectangular form?

1 Answer
Feb 12, 2016

# x^2 + y^2 - 6x - 4y = 0#

Explanation:

using the formulae that links Polar to Rectangular coordinates.

#• r^2 = x^2 + y^2 #

#• x = rcostheta rArr costheta = x/r #

#• y = rsintheta rArr sintheta = y/r #

in the above question then

# r = 6.(x/r) + 4.(y/r) #

( multiplying both sides by r )

# r^2 = 6x + 4y#

# rArr x^2 + y^2 -6x - 4y = 0 #

which is the equation of a circle : centre(3,2 ) and # r =sqrt13 #