What is msu?
a. 49
b. 77
c. 98
d. 161

The measure of an angle formed by a tangent and a secant intersecting outside the circle is equal to one-half the difference of its intercepted arcs. 

T = 1/2 (RU - SU)
21 = 1/2(119 - SU)
42 = 119 - SU
77 = SU

The answer is B. 77

Hope this helps =)

X^2 - 4x +(4/2^2) + y^2 + 8y + (8/2^2) = -4 + (4/2^2) + (8/2^2)(x + 2)^2 + (y + 4)^2 = -4 + 4 + 16your center is (-2, -4) and the radius is the sqrt of -4 + 4 + 16 which is 4