A circle is a perfectly symmetric object. Can you guess what kind of equation creates a circle?
(Remember the equation of a parabola was
Try out different equations on DESMOS and see which one makes a circle. Attach a screenshot of your trials here.
The boundary of a circle is called the circumference of a circle and the length of the circumference is given by
Where
C - Circumference
r - Radius of the circle
You will always notice π when measuring things related to circles and it measures 3.14.
Find the circumference of a circle whose radius is 9 cm.
Find the circumference of a circle whose diameter is 5 inches.
Find the radius of a circle whose circumference is 200 cm.
The flat space occupied by a circle is called the area of a circle and is given by
Where
A - Area
r - Radius of the circle
You will always notice π when measuring things related to circles and it measures 3.14.
Find the area of a circle whose radius is 9 cm.
Find the area of a circle whose diameter is 5 inches.
Find the radius of a circle whose area is 360 m^2.
Match each definition with a part of the circle.
A diameter is a chord that passes through the center of a circle.
A secant is a line that intersects a circle at two points.
A tangent is a line that touches a circle at only one point.
A chord is a line segment with its endpoints on a circle.
Match the following definitions with the parts of the circle in the diagram.
