Tangent is drawn from a point P to a circle, which meets the circle at T such that PT = 8 cm. A secant PAB intersects the circle in points A and B. If PA= 5 cm, what is the length (in cm) of the chord AB?
Answer & explanation
Correct answer: option 4
\( {PT }^{2} \) = PA x PB
= \( {PT }^{2} \) = 5 x PB
= 64 = 5PB
= PB = 12.8cm
Then,
AB = (12.8 - 5) = 7.8 cm.