Question

if the blue radius below is perpendicular to the green chord and the segment $overline{ab}$ is 8.5 units long, what is the length of the chord? a. 34 units b. 8.5 units c. 4.25 units d. 17 units

Explanation:

Step1: Recall circle - chord property

A radius perpendicular to a chord bisects the chord.

Step2: Calculate chord length

Since $\overline{AB}=8.5$ units and the radius bisects the chord, the length of the whole chord $\overline{AC}=2\times\overline{AB}$.
So, $\overline{AC}=2\times8.5 = 17$ units.

Answer:

D. 17 units