Question 875466
base is an equilateral triangle with a height of 12.1244
area of the base is equal to 1/2 * b * h which is equal to 1/2 * 14 * 12.1244 which is equal to 84.8708
the triangular pyramid has 3 faces.
each face has a height of 20 and a base of 14.
area of each face is equal to 1/2 * 14 * 20 = 140
the sum of the area of the faces is equal to 3 * 140 = 420
the total surface area is equal to the area of the base plus the area of the faces which is equal to 87.8708 + 420 which is equal to 504.8708 which rounds to 504.9 if you want the answer to one decimal place.
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