Answer:
a) 156.25 cm^2 b) 221.67 cm^2 c) 65.42 cm^2
Explanation:
a)
We know that the formula for the area of a quadrilateral is Length x Height (A = LH).
Since the length and height of a square is the same, L = 12.5cm and H = 12.5cm.
So we incorporate our formula for the area of a square into this situation:
A = 12.5 x 12.5
A = 156.25 cm^2
b)
We know that the formula for the area of a circle is Pi x radius squared (A = πr^2).
Since we know that the diameter of the circle is 16.8cm, we will use this to find the radius.
Radius can be found by halving the diameter (r = d/2).
So we incorporate our formula for radius into this situation:
r = 16.8/2
r = 8.4cm
Now that we have our radius, we can find the area of our circle.
So we incorporate our formula for the area of a circle into this situation:
A = π(8.4)^2
A = 221.6707776 = 221.67 cm^2
c)
We can see from the diagram that the shaded portion come mainly from the circle. So to find the area of the shaded part, we can simply subtract the area of the square, from the area of the circle (A of circle - A of square = Area of shaded part).
So we incorporate our formula for the area of the shaded part into this situation:
A = 221.67 cm^2 - 156.25 cm^2
A = 65.42 cm^2