S and T are points on sides PR and QR of PQR such that . Show that RPQ RTS.
In RPQ and RTS,
(Common angle)
(Given)
Therefore, by AAA similarity criterion, RPQ RTS.
Explanation
This question tests the AAA similarity criterion. When two triangles share a common angle and have another pair of equal angles, all three corresponding angles become equal, making the triangles similar.
The key insight is recognizing that is common to both triangles RPQ and RTS, and combining this with the given condition establishes the similarity.
Solution Steps
Step 1: Identify that is common to both triangles RPQ and RTS.
Step 2: Note the given condition: .
Step 3: Apply AAA similarity criterion — since two angles are equal, the third angle is also equal (by angle sum property).
Step 4: Conclude that RPQ RTS by AAA similarity criterion.