Area of Triangle

Area=SQRT(s(s-a)(s-b)(s-c))
where s=(a+b+c)/2 or perimeter/2

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The SUM of TWO SIDES MUST ADD UP TO BE GREATER THAN THE LENGTH OF THE REMAINING THIRD SIDE.
OR (with sides A,B,C):

• A + B > C,
• B + C> A,
• and A + C>B

So, can you have a triangle with sides 5, 12, 16?
How about 5, 12, 13? What does this look like?
Interestingly heron's formula also leads us to a result where we can calculate the height of a triangle. With base c and height h the height is,

h =

2

(SQRT(s(s-a)(s-b)(s-c))