Question

Convert to rectangular form r=4 cos theta

Answer 1

Hello,

x=r cos t
y=r sin t
x²+y²=r²

r=4 cos t
r=4x/r==>x²+y²=4x
==>(x-2)²+y²=4 (a circle center (2,0),radius 2)

Answer 2

r^2 = 4r costheta
x= r costheta
y=rsin thta
r^2 = 4x
x^2+y^2 = 4x
r^2=x^2+y^2

x^2+y^2=4x
x^2+4x+y^2=0
x^2-4x+4 +y^2=4
(x-2)^2+y^2 = 4