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1 vote
10 In the

accompanying diagram, PA is tangent to
circle O at A and PBC is a secant. If CB = 9 and
PB = 3, find the length of PA.
C

8
A
a
CB=9
PB = 3
PA=X
5

10 In the accompanying diagram, PA is tangent to circle O at A and PBC is a secant-example-1
User Pimgd
by
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1 Answer

6 votes

Answer:

PA = 6

Explanation:

given a tangent and a secant drawn from an external point to the circle , then the square of the tangent is equal to the product of the secant's external part and the entire secant , that is

PA² = PB × PC = 3 × (3 + 9) = 3 × 12 = 36 ( take square root of both sides )

PA =
√(36) = 6

User Arun Blr
by
8.0k points