Answer:
D. 264°
Explanation:
When a tangent and a secant, two secants, or two tangents intersect outside a circle then the measure of the angle formed is one-half the positive difference of the measures of the intercepted arcs. Therefore,
60° = 1/2[(18x - 6)° - (5x +17)°]
60° * 2 = (18x - 6 - 5x - 17)°
120° = (13x - 23)°
120 = 13x - 23
120 + 23 = 13x
143 = 13x
143/13 = x
11 = x
x = 11
(18x - 6)° = (18*11-6)°= (198 - 6)° = 192°
(5x +17)° = (5*11 +17)° =(55+17)° = 72°
m (arc KNL) = (18x - 6)° + (5x +17)° = 192° + 72°
m (arc KNL) = 264°