Posted by Mallory on Monday, December 20, 2010 at 10:33pm.
When in STD position, the center i8s at
the origin:
C(h , k),
C(0 , o), P(-3 , 4),
r^2 = (x - h)^2 + (y - k)^2,
r^2 = (-3 - 0)^2 + (4 - 0)^2,
r^2 = 9 + 16 = 25,
r = 5.
rcos(theta) = x -h = -3 -0 = -3,
5cos(theta) = -3,
cos(theta) = -3/5 = -0.6,
theta = 126.9 deg.
Sec(theta) = 1/cos(theta) = 1/-0.6 =
-1.67.