A triangular park has sides and (see Figure) gardener Dhania has to put a fence all around it and also plant grass inside. How much area does she need to plant? Find the cost of fencing it with barbed wire at the rate of Rs per metre leaving a space wide for a gate on one side.
A traffic signal board, indicating 'SCHOOL AHEAD', is an equilateral triangle with side ′a′. Find the area of the signal board, using Heron’s formula. If its perimeter is , what will be the area of the signal board?
The triangular side walls of a flyover have been used for advertisements. The sides of the walls are and . The advertisements yield an earning of Rs per per year. A company hired one of its walls for months. How much rent did it pay?