Calculate the area of a triangle with sides 7 cm, 9 cm and 12 cm.
7 cm, 9 cm और 12 cm भुजाओं (Side) वाले त्रिभुज (Triangle) के क्षेत्रफल (Area) की गणना कीजिए।
Answer और ExplanationAnswer and explanation
Answer: (C) 14√5 cm²
अर्धपरिमाप (Semi-perimeter) s = 7 + 9 + 122 = 14
s − a = 7, s − b = 5, s − c = 2
हीरोन सूत्र (Heron's formula) से क्षेत्रफल (Area) = √14 × 7 × 5 × 2 = √980 = √196 × 5 = 14√5 cm²
✓
क्षेत्रफल 14√5 cm² है।
s = 7 + 9 + 122 = 14
s − a = 7, s − b = 5, s − c = 2
Area = √14 × 7 × 5 × 2 = √980 = √196 × 5 = 14√5 cm²
✓
The area is 14√5 cm².
Source: Selection Post Phase XIV (12th) · 17 Sep 2026 · Shift 2। Solution: Prashant Sir, Vijayastra।Source: Selection Post Phase XIV (12th) · 17 Sep 2026 · Shift 2. Solution by Prashant Sir, from Vijayastra.