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From an external point
MATHEMATICS · Multi-part · CBSE · Mathematics · Circles · Circles
Problem
From an external point
P
P
P
, two tangents
P
A
PA
P
A
and
P
B
PB
P
B
are drawn to a circle with centre
O
O
O
and radius
4
cm
4\,\text{cm}
4
cm
. (a) Prove that
P
A
=
P
B
PA = PB
P
A
=
P
B
. (b) If
O
P
=
10
cm
OP = 10\,\text{cm}
O
P
=
10
cm
, find the common length of the tangents. (c) Hence, find the perimeter of the quadrilateral
O
A
P
B
OAPB
O
A
P
B
.
Related theory
Pythagoras' Theorem
Triangle Properties
Circles
Tangent length properties
Number of tangents from a point
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