SOLUTION: A triangle with the length of 5cm on each side

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Question 1084696: A triangle with the length of 5cm on each side
Answer by MathLover1(20849) About Me  (Show Source):
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A triangle with the length of 5cm on each side is an equilateral triangle;
its perimeter is P=5cm%2B5cm%2B5cm=15cm
and its area is A=%281%2F2%29%2A5cm%2Ah
to find h use right angle triangle whose legs are h and 5cm%2F2=2.5cm and hypotenuse is 5cm
%285cm%29%5E2=%282.5cm%29%5E2%2Bh%5E2
25cm%5E2=6.25cm%5E2%2Bh%5E2
25cm%5E2-6.25cm%5E2=h%5E2
18.75cm%5E2=h%5E2
h=sqrt%2818.75cm%5E2%29
h=4.330127018922193cm
A=%281%2F2%29%2A5cm%2A4.330127018922193cm
A=10.82531754730548cm%5E2
A=10.83cm%5E2