Multiple choice

In a circle with center O, AB is a chord and PQ is a tangent at point T on the circle. The chord AB is extended to meet the tangent PQ at point P. If AB = 9 cm and BP = 16 cm, what is the length of the tangent PT?

  1. 30

  2. 20

  3. 40

  4. 50

  5. 34

Reveal answer Fill a bubble to check yourself
B Correct answer
AI explanation

Applying the tangent-secant theorem, the square of the tangent length equals the product of the external secant segment and the entire secant length. The entire secant length PA is the sum of PB and AB, which is 16 + 9 = 25 cm. Setting up the equation PT^2 = PB * PA gives PT^2 = 16 * 25 = 400, so PT = 20 cm.