The diameter of a circle refers to a straight line passing from side to side through the center connecting to points in the circumference. In the other hand the radius is a line passing through the center of the circle to the circumference, and it is the half of the measure of the diameter.
On this question is given that the diameter of a circle is 2 yards and it is asked to find the radius.
The answer is The formula for the area of a parallelogram is A = bh, and the formula for area of a triangle is A = 1/2bh. Since a triangle is half of the area of a parallelogram with the same base and height, the only difference in the formula is 1/2.
