Question

3. Make a table of length of the side of an equilateral triangle and its perimeter by taking four different lengths and draw the side-perimeter graph. From the graph, read the following:
(1) perimeter, when the side is 2.5 units.
(2) length of side, when perimeter is 10.5 units.​

Answer 1

when the side is 2.5 units

Answer 2

Made the required table

perimeter of equilateral triangle with side = 2.5 units is 7.5 units

If perimeter of equilateral triangle is 10.5 m then each side of triangle will be 3.5 m

•Equilateral triangle is triangle in which all sides of it are equal

•so let a side of equilateral triangle is x

•Now, perimeter = sum of all sides

perimeter of equilateral triangle will be side + side + side i.e. 3 × side

•Perimeter of equilateral = 3×side

triangle

•Perimeter of equilateral = 3x

triangle

•Now required table is

side of triangle 1 , 2 , 3 , 4

Perimeter 3 , 6 , 9 , 12

•From graph it is calculated that

1) perimeter of equilateral triangle with side = 2.5 units is 7.5 units

2) If perimeter of equilateral triangle is 10.5 m then each side of triangle will be 3.5 m