Question

The perimeter of an equilateral triangle is 27 cm. Find the area of the triangle, if its heightis 7.8 cm.

Answer 1

Answer:

an equilateral triangle with a perimeter

of 27 cm will have 3 sides = 9cm.

A line drawn from the midpoint of the

triangles base up to the highest apex

will construct a right angled triangle

of base = 4.5 cm and hypotenuse = 9 cm

The vertical side^2 = hypotenuse^2 - base^2

Vertical side^2 = 9^2 - 4.5^2

Vertical side^2 = 81 - 20.25

Vertical side = sqrt%2860.75%29

Vertical side = 7.8 cm

Area of equilateral = 1/2(base * height)

Area of equilateral = 1/2(9 * 7.8)

Area = 35.1 cm^2

Hope this helps.