Question

If perimeter of an equilateral is 90 then find its area.

Plz write answer step by step....

Answer 1

Answer:

root675 units

Step-by-step explanation:

given:perimeter =90 units

each side =90/3

=30units.

Area = root 3/4 a2

=root 3/4 ×30×30

=root3/4 ×15×15

=root675units(Answer)

Answer 2

Answer:

Step-by-step explanation:

We know that an equliateral triangle has all 3 sides congruent, so each side is equal to 90/3, so each side is equal to 30.

Then we need to draw a line down the middle, which is the alititude to find the height so we can find the area of the triangle.

The altitude bisects the line segment it intersects with in half, so we can find out that the triangle that the altitude creates is a 15 by 30 by x(the alitude)

We can now use the pyth. thereum because the alititude is perpendicular to the line it intersects with

So 15^2+x^2=30^2, solve this equation out and x will end up being 25, so the height of the triangle is equal to 25

Now the area of a triangle is equal to (b*h)/2. Plug in the base, which will be 30, and the height and divide by 2 and that will be your area

(25*30)/2=375

Area= 375 units^2