Question

What is the length of AC?
A
8
B
C
O

Answer 1

16

Explanation:

Theorem: In a circle, if a radius is perpendicular to a chord, then the radius is the perpendicular bisector of the chord.

In this case, the radius containing points O and B is perpendicular to chord AC, so the radius bisects chord AC making AB = BC.

Also,

AB + BC = AC

By substitution, we have

AB + AB = AC

AC = 2AB

AC = 2(8)

AC = 16

Answer 2

hi, it's 16 because:

`ab = bc \\ ab = 8 \\ ac = 2 * 8 = 16 \\ ac = 16`