Question: In triangle DEF, if DE = 6 cm, DF = 8 cm, and EF = 10 cm, what is the area of triangle DEF?
Options:
Correct Answer: 30 cm²
Solution:
Using Heron\'s formula, the semi-perimeter s = (6 + 8 + 10) / 2 = 12 cm. Area = √[s(s-a)(s-b)(s-c)] = √[12(12-6)(12-8)(12-10)] = √[12*6*4*2] = √576 = 24 cm².