Find the area of an equilateral triangle with height of 9 inches.?

Question

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Answer 1

In an equilateral triangle the ratio of the height to the base is rt3/2
rt3/2=9/b, b=18/rt3
Area =1/2 b X h
Area=1/2(18/rt3) X 9
=81/rt3, =81rt3/3, =27rt3

Answer 2

All angles are 60°
Vertical height = 9 ins
x = 1/2 base
tan 60° = 9 / x
x = 9 / tan 60°
x = 9 / √3
Area = ( 9 /√3 ) ( 9 ) in ²
Area = 81 / √3 in ²
Area = 81√3 / 3 in ²
Area = 27 √3 in ²