Quandaries and Queries


I'm working on an Algebra 2 problem from my text. I'm going into tenth
grade and I have a triangle who's sides measure 3ft, 4ft, and 5ft. I
need to find the area however I don't know the height, or how to get it.
If you could send me the formula that would be fantastic. Thanks so
much for your help!




Hi Barkie,

The short answer is that a triangle whose sides are 3, 4, 5 is a right triangle with legs 3 and 4 -- it's area is 1/2(3*4) = 6. This is true since

32 + 42 = 52

In general, for the area of a triangle given the sides a, b, and c, one would use Heron's formula for the area:

First compute the semiperimeter

(3 + 4 + 5)/2 = 6.


A = sqrt(6*3*2*1) = 6.



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