Question

Find the area of an equilateral triangle with side length 9.2 cm. Round your answer to 1 DP.

Answer 1

Area=36.66 cm^2

Explanation:

First, you need the height.

Use the Pythagorean theorem:

hypotenuse^2=height^2+(1/2 base)^2

It's one-half base because it's an equilateral triangle.

1/2 base =4.6

(9.2)^2-4.6^2=height^2

84.64-21.16=height^2

height^2=63.48

height=7.97

Area=(1/2)(base)(height)

Area=(1/2)(9.2)(7.97)=36.66 cm^2