Since the triangle is equilateral, all of its interior angles have a measure of 60º.
Substract the area of the triangle from the area of a circular sector with radius 7cm enclosed by an angle of 60º to find the area of the shaded region.
The area of an equilateral triangle with side length L is:
The area of a circular sector of radius r enclosed by an angle of θ degrees is:
Replace θ=60 and r=7cm to find the area of the circular sector:
Replace L=7cm to find the area of the triangle:
Then, the area of the shaded region is:
Therefore, the area of the shaded region to 3 significant figures, is: