pove that
The length of two tangent drawn
from an external point
to
a circle are equal
Answers
Answer:
Given: A circle with centre O; PA and PB are two tangents to the circle drawn from an external point P.
To prove: PA = PB
Construction: Join OA, OB, and OP.
It is known that a tangent at any point of a circle is perpendicular to the radius through the point of contact.
OA⊥PA
OB⊥PB
In △OPA and △OPB
∠OPA=∠OPB (Using (1))
OA=OB (Radii of the same circle)
OP=OP (Common side)
Therefor △OPA≅△OPB (RHS congruency criterion)
PA=PB
(Corresponding parts of congruent triangles are equal)
Thus, it is proved that the lengths of the two tangents drawn from an external point to a circle are equal.
The length of tangents drawn from any external point are equal.
Answer:
☆ ANSWER ☆
LETS TAKE THE TANGENTS AP AND BP WHERE P IS THE EXTERNAL POINT OF THE CIRCLE WITH CENTER O.
JOIN OP.
LETS TAKE TRIANGLE AOP AND BOP.
< OAP = < OBP = 90 (TANGENT TO THE CIRCLE)
OP = OP ( COMMON )
OA = OB ( RADIUS )
THEREFORE
TRIANGLE AOP AND BOP ARE CONGRUENT BY RHS CONGRUENCE RULE.
THEREFORE,
C.P.C.T.
AP = BP
HENCE PROVED
HOPE IT HELPS