ASA(angle side angle):
Two Triangles are congruent if two angles
and the included side of One triangle are equal to two angles & the
included side of the other triangle.
Alternate angles:
When two lines are crossed by another line the
pair of angles on opposite sides of the transversal is called alternate angles.
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Use the properties of a transversal
intersecting two Parallel Lines i.e, interior angles are equal to each other,
to show congruence of given Triangles.
Given,
l || m and p || q
To prove,
ΔABC ≅ ΔCDA
Proof,
In ΔABC and ΔCDA,
∠BCA =
∠DAC
(Alternate interior angles as p||q)
AC = CA (Common)
∠BAC =
∠DCA
(Alternate interior angles as l ||m)
Hence, ΔABC ≅ ΔCDA (by ASA congruence rule.)
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