Richard0715 wrote:

The height of an equilateral triangle splits the triangle into two 30-60-90 triangles (Each 30-60-90 triangle has sides in the ratio of 1: square root of 3: 2). Because of this, the area for an equilateral triangle can be expressed in terms of one side. If we call the side of the equilateral triangle, s, the height must be (s multiplied by square root of 3) / 2 (using the 30-60-90 relationships).

Can someone explain why the height which is the square root of 3 is being divided by 2? The explanation then states... "The area of a triangle = 1/2 × base × height, so the area of an equilateral triangle can be expressed as: 1/2 × s × (s multiplied by square root of 3) / 2 .

The question i pulled this from is asking about the area of the triangle. MGMAT's explanation does not make sense to me of why the height is being divided by 2 initially.

Thanks!!!!!!

In order to solve your problem, we need to learn some basic formulas related to the area of a triangle.

1. Area of a triangle A = (1/2)*base*height

2. Area of a triangle A = sq.rt(s*(s-a)*(s-b)*(s-c)) where s= (a+b+c)/2

In an equilateral triangle all sides are equal. So s=3a/2. Where a is the side of the triangle

Per second point, A = (sq.rt(3)/4)*a^2

Per 1st point , A = a*height/2

If you compare both of them you will get the height.

Hope this clears your confusion.

Give kudos if you find the answer helpful