An equilateral triangle has a perimeter of 48 cm. What is the area?

Step-by-step explanation:

we know that

An equilateral triangle has three equal sides and three equal interior angles (each interior angle measure 60 degrees)

so

The perimeter is equal to

where

b is the length side of the equilateral triangle

we have

substitute

solve for b

Find the area

The formula of area applying the law of sines is equal to

substitute the value of b

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so: