Mathematics

Grade6

Easy

Question

# What is the perimeter of an equilateral triangle if the length of the side is 3x m?

- 9 m
- 10 m
- 9x m
- 10x m

Hint:

### In this question, we are given a term. It is a side of an equilateral triangle. We are asked to find the perimeter of the triangle. Perimeter means the length of the boundary of the given shape. We have to find the right operation using the given term to find the perimeter of the triangle.

## The correct answer is: 9x m

### The given value for the length of the side of an equilateral triangle is 3x m

Length = 3x m

We have to find the perimeter of an equilateral triangle. We know that perimeter means the total length of the boundary of the shape. As an equilateral triangle has all three sides equal, we will have to add them to get the length of complete boundary, or in other words a perimeter. As an equilateral triangle has all sides equal. So to find a perimeter we will have to add the side 3 times, or simply multiply the side by 3.

The formula for the perimeter of the triangle will be

Perimeter = 3(length)

Substituting the respective values, we get

Perimeter = 3(3x)

As there are two with the same variable, we can add them directly like normal numbers.

Perimeter = 9x m

Therefore, the perimeter of the triangle will be 9x m

So option which is ‘9x m’, is the right option.

For such questions, we should remember the formulas of area and perimeter of different shapes. We should be careful about the different variables too.