Question

find the measure of the arc or angle indicated. assume that lines which appear tangent are tangent. just enter the number.

Answer 1

C. 60°

Explanation:

The vertical angle formed inside a circle when two chords intersect each other is equal to half the sum of the measures of the intercepted arcs, based on the intersecting chords angle measure theorem.

Thus:

90° = ½(120° + arc TA)

Multiply both sides by 2

2*90 = 120 + arc TA

180 = 120 + arc TA

Subtract 120 from each side

180 - 120 = arc TA

60° = arc TA

Arc TA = 60°