SOLUTION: an equilateral triangle of side length of 6cm is cut from a sheet of cardboard. a circle is hen cut out of the triangle leaving a hole of diameter of 2 cm what is the cardboard rem

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Question 985413: an equilateral triangle of side length of 6cm is cut from a sheet of cardboard. a circle is hen cut out of the triangle leaving a hole of diameter of 2 cm what is the cardboard remaining
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
That triangle is composed of two 30-60-90 special triangles.

a%5E2%2B3%5E2=6%5E2
a%5E2=36-9
a%5E2=27
a=3sqrt%283%29
The equilateral triangle has area, before the circular cut, of %281%2F2%296%2A3sqrt%283%29=9sqrt%283%29.

Cut out the circular piece from the interior,
9sqrt%283%29-pi%2A2%5E2
highlight%289sqrt%283%29-4pi%29