The perimeters of two equilateral triangles are in the ratio 9:1 what is the ratio of their areas?

The ratio of their area is 81 : 1.

Step-by-step explanation:

Given,

The perimeter of two equilateral triangles is 9:1

To find the ratio of their areas.

Formula

If each side of a equilateral triangle is a then perimeter = 3a and area = a²

Now,

Perimeter of the 1st triangle is 9x

So, each side will be 3x

Again,

Perimeter of the 2nd triangle is x

So, each side will be

Now,

Area of the 1st triangle =(3x)²

Area of the 2nd triangle = ()²

Hence,

The ratio of their area = (3x)² :  

= 9x² :

= 81 : 1

Thus the obtained ration of the triangle is 81:1

the answer is b

answer is  

a.

p = 78

step-by-step explanation: