SaiBook.us Geometry

Lesson

Title: Area of Circle

Grade: 6-a Lesson: S2-L1

Explanation: Hello students, let us learn a new topic in geometry today with definitions, concepts, examples, and worksheets included.

Lesson:

Definition: Circle

A circle is a round figure with no corners or edges, made of a curved line.

This line segment is called the diameter of the circle.

$1$

Explanation: In this image, the parts of a circle are radius(r), diameter(d), chord(c), tangent(t).

Definition: Area of Circle

The area of a circle is the amount of space enclosed by the circle’s boundary. It is the total surface or space within the circular shape.

This area can be calculated using the formula: \$ A = πr^2\$

A = area of circle

r = radius of circle

π (pi) is a mathematical constant approximately equal to 3.14159.

The diameter of a circle is twice the radius (d = 2r) and can be used to calculate the radius \$(r = d/2)\$.

$2$

Explanation: The image illustrates the area of a circle with a radius r.