Advertisements
Advertisements
प्रश्न
Find the area of an equilateral triangle whose perimeter is 180 cm
Advertisements
उत्तर
Perimeter of an equilateral triangle = 180 cm
3a = 180
a = `180/3`
= 60 m
Area of an equilateral triangle
= `sqrt(3)/4 "a"^2 "sq.unit"`
= `sqrt(3)/4 xx 60 xx 60 "sq.m"`
= `sqrt(3) xx 15 xx 60 "sq.m"`
= 1.732 × 15 × 60 sq.m
= 1558.8 sq.m
Area of an equilateral triangle = 1558.8 sq.m
APPEARS IN
संबंधित प्रश्न
The triangular side walls of a flyover have been used for advertisements. The sides of the walls are 122m, 22m, and 120m (see the given figure). The advertisements yield an earning of ₹ 5000 per m2 per year. A company hired one of its walls for 3 months. How much rent did it pay?

There is a slide in the park. One of its side walls has been painted in some colour with a message “KEEP THE PARK GREEN AND CLEAN” (see the given figure). If the sides of the wall are 15m, 11m, and 6m, find the area painted in colour.

A hand fan is made by stitching lo equal size triangular strips of two different types of paper as shown in Fig. 12.28. The dimensions of equal strips are 25 cm, 25 cm and 14 cm. Find the area of each type of paper needed to make the hand fan.

Find the area of the triangle formed by the points
(1, – 1), (– 4, 6) and (– 3, – 5)
Determine whether the sets of points are collinear?
(a, b + c), (b, c + a) and (c, a + b)
Find the area of triangle AGF
Using Heron’s formula, find the area of a triangle whose sides are 10 cm, 24 cm, 26 cm
The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to its base is 3 : 2. Find the area of the triangle.
Find the area of a parallelogram given in figure. Also find the length of the altitude from vertex A on the side DC.

In the following figure, ∆ABC has sides AB = 7.5 cm, AC = 6.5 cm and BC = 7 cm. On base BC a parallelogram DBCE of same area as that of ∆ABC is constructed. Find the height DF of the parallelogram.

