140 likes | 262 Views
EQ: How can you use the parts of a circle to solve for the circumference. By: Casie Pease / Moving Forward 6 th Grade . A circle is a shape with all points the same distance from its center. A circle is named by its center. .
E N D
EQ: How can you use the parts of a circle to solve for the circumference. By: Casie Pease / Moving Forward 6th Grade
A circle is a shape with all points the same distance from its center. A circle is named by its center.
The distance across a circle through the center is called the diameter. A real-world example of diameter is a 9-inch plate.
The radius of a circle is the distance from the center of a circle to any point on the circle.
A chord is a line segment joining two endpoints that lie on a circle. • The circle to the right contains chord AB.
What is significant about the diameter of a circle versus a chord?
Name the center of the circle Point B
Name two chords that are not the diameter of the circle. DE and FG
What are AC and Dg? Diameters of the circle
Name radii of the circle? BA, BC, BG, DB
Explain why DG is both a diameter of the circle and a chord.
DISCOVERIng Perimeter • AKA Circumference • Fill in the measurements of the radius, diameter and perimeter for each circle. • Find a pattern using the diameter and the perimeter of the circle. • Is there a relationship? • Is there a relationship between the radius and perimeter?
Students need to work on chart • Derive an expression (formula) that can be used to find the circumference (perimeter ) of a circle.
CIRCUMference • Perimeter of a circle (distance around) • Circumference = d x p • Circumference = pr2 (PI X RADIUS X SQUARED)