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Remark:
Given two angles of a triangle, you can always find the third angle of the triangle. So,
whenever, two angles and one side of one triangle are equal to the corresponding two
angles and one side of another triangle, you may convert it into ‘two angles and the
included side’ form of congruence and then apply the ASA congruence rule.

2) RHS Congruence criterion: If under a correspondence, the hypotenuse and one side of
a right-angled triangle are respectively equal to the hypotenuse and one side of another
right-angled triangle, then the triangles are congruent.

EXAMPLE: Given below are measurements of some parts of two triangles. Examine
whether the two triangles are congruent or not, using RHS congruence rule. In case of
congruent triangles, write the result in symbolic form.
In ∆ABC ∠B = 90°, AC = 8 cm, AB = 3 cm
In ∆PQR ∠P = 90°, PR = 3 cm, QR = 8 cm

SOLUTION: (i) Here, ∠B = ∠P = 90º,
hypotenuse AC = hypotenuse RQ (8 cm)
side AB = side RP ( = 3 cm)
So, ∆ABC ≅ ∆RPQ (By RHS Congruence rule)