rcsc(theta) = 3
r/sin(theta) = 3
r =3sin(theta)
Now use the relation between polar coordinates and rectangular coordinates
x = rcos(theta)
y = r sin(theta)
=> x = [3sin(theta)]cos(theta)
x = 3 sin(theta)cos(theta)
and y = [3sin(theta)]sin(theta)
y = 3 [sin(theta)]^2