Triangle given by sums or excesses of pairs of sides: find sides, then area

This type of question, asked 2 times: CDS 1 2025, CDS 2 2026. All 2 questions below, oldest first.

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Question 1
CDS 1 2025
16 $In a triangle ABC, AB + BC = 7.1 cm, BC + CA = 12.1 cm and CA + AB = 7.2 cm. What is the area of the triangle ?$
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Question 2
CDS 2 2026
54 $ABC is a triangle in which (AB + BC) exceeds CA by 10 cm, (BC + CA) exceeds AB by 8 cm and (CA + AB) exceeds BC by 72 cm. What is the area of the triangle ?$
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