Circle Area
A circle is a shape where all points are the same distance from the center of the circle. The radius (r) of a circle is the distance from the center of the circle to any point on the circle. The diameter (d) of a circle is the distance across the circle through the center.
Area (A) is the number of square units it takes to cover the surface of a shape. Area is expressed in square units such as cm2, in2, or ft2.
Example 1: Area answer in terms of π
Find the area in terms of π. Type "pi" in for π so that a correct answer would look like 7pi sq m Area: The diameter of the circle is 3 yd. To calculate the area of the circle, we will first find the radius of the circle. d = 2 r r = = = 1.5 yd Now we are ready to calculate the area of the circle. A = π r 2 = π (1.5 yd)2 = π (2.25 yd2) = 2.25π yd2 The answer is Area:
The diameter of the circle is 3 yd. To calculate the area of the circle, we will first find the radius of the circle.
Example 2: Area answer with π = 3.14
Find the area. Use 3.14 as an approximation for π. A correct answer would look like 14.5 sq cm. Using the same problem as Example 1, we know that the area A A = 2.25π yd2 = 2.25(3.14) yd2 = 7.065 yd2 The answer is Area:
Using the same problem as Example 1, we know that the area A
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