# ML Aggarwal CBSE Solutions Class 6 Math Twelveth Chapter Algebra Exercise 12.2

### ML Aggarwal CBSE Solutions Class 6 Math 12th Chapter Algebra Exercise 12.2

Ex 12.2

(1) If the side of an equilateral triangle is l, then express the perimeter of the triangle in terms of l.

Solution: In equilateral triangle all the sides are equal.

There are 3 sides in a triangle

One side of the triangle = l

Then, the perimeter of the triangle = 3 x l = 3l

(2) The side of a regular hexagon is l. Express its perimeter in terms of l.

Solution: In regular hexagon there are total 6 sides and all the sides are equal.

One side of regular hexagon here is l.

So the perimeter of a regular hexagon = 6 x l = 6l

Ans. 6l

(3) The length of an edge of a cube is l. Find the formula for the sum of lengths of all the edges of the cube.

Solution: There are total of 12 edges in an cube.

Here, the length of an edge of a cube is l.

Then, the sum of lengths of all the edges of the cube = 12 x l = 12l

(4) If the radius of a circle is r units, then express the length of a diameter of the circle in terms of r.

Solution: Here the radius of a circle is r units.

Then the length of a diameter of the circle in terms of r units = 2 x r = 2r