DE is a chord and KDE is a secant of a circle. If KD = 9 cm, DE = 7 cm and KH is a tangent to the circle at point H, then find KH.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e. 12 cm.
We know that,
If a tangent and a secant are drawn from a common point outside the circle then,
⇒ KH2 = KD × KE
Now, according to the question
⇒ KH2 = 9 × (7 + 9)
⇒ KH2 = 9 × 16
⇒ KH2 = 144
⇒ KH = 12
Hence, KH = 12 cm