Quandaries and Queries


What is the area of a triangle with dimensions 3"X5"X7"? Could you provide the formula? Sorry, I have a degree in math and answered 7.5 in. sq., but was told the correct answer is 6.5 in. sq.


Hi Perry,

The formula you need is Heron's Formula, it is an expression for the area of a triangle, given the lengths of the three sides. Using Heron's Formula for your triangle I get

area = Sqrt[ 15/215/2 - 3)( 15/2 - 5)( 15/2 - 7)] = 15 Sqrt(3)/4 = 6.495 square inches.



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