There are 10 such equal triangles if the decagon is regular.
Area of 1 triangle = 161/10 = 16.1 square inches.
Area of a triangle = 1/2 * b * h
area = 16.1
base = 4.6 (the length of each side)
16.1 = 1/2 * 4.6 * h
32.1 = 4.6 * h
h = 32.1 / 4.6
h = 6.98 inches. <<<< answer
