Question

Chords and Arcs: What is the measure of AC?
(3x – 1.5) (3x+9)

Answer 1

21°

Explanation:

The measure of arc AC is twice the measure of the inscribed angle ABC, thus

3x + 9 = 2(3x - 1.5) ← distribute

3x + 9 = 6x - 3 ( subtract 6x from both sides )

- 3x + 9 = - 3 ( subtract 9 from both sides )

- 3x = - 12 ( divide both sides by - 3 )

x = 4

Thus

arc AC = 3x + 9 = 3(4) + 9 = 12 + 9 = 21°