An interactive applet and associated web page that demonstrate the the concept of adjacent arcs. The user can 3 drag points around a circle that define the endpoints of two adjacent arcs. Web page has the properties of adjacent arcs. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

An interactive applet and associated web page that demonstrate the concept of an arc. The applet shows a circle with part of it highlighted to identify the arc. Each endpoint of the arc can be dragged to resize it. The web page has definitions and links to the properties of an arc. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

An interactive applet and associated web page that demonstrate the concept of arc length. The applet shows a circle with part of its circumference highlighted and the central angle shown. As the user drags either end of the arc it is redrawn and the calculation for arc length changes as you drag. The text on the web page gives the formula for calculating the arc length. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

An interactive applet and associated web page that demonstrate the concept of the peripheral angle (inscribed angle) of an arc. This is the angle subtended at the circle circumference of an arc. The applet shows an arc with draggable end points and the angle it subtends at the circumference. It is seen that this angle is constant for a constant arc length. It shows also what happens when the vertex is inside the arc that subtends it The web page has links to other arc properties and a formula for the subtended angle for a given arc length. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

The purpose of this lesson is to discover the properties of inscribed angles, central angles and to use them to solve situational problems.

Included is a YouTube video to support Grade 9 Blended Learning Math - Unit 8.3: Circle Geometry - Properties of Angles in a Circle.

An interactive applet and associated web page that demonstrate the concept of the intercepted arc - 'That part of a circle that lies between two lines that intersect it'. The applet shows a circle with part of it's circumference highlighted and the central angle shown. As the user drags either end of the arc it is redrawn and the intercpted arc changes. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

The following file contains the assets (or resources) to accompany the Sask DLC Grade 9 Mathematics. Please note that this is not the content of the course, but the assets used to support and deliver it. The files are organized in a zipped folder. You can download it and extract the files. Links are also provided to other materials like videos and other suggested resources. 

An interactive applet and associated web page that describe the radius of an arc and how to derive it from the width and height of the segment defined by that arc. A practical use is described for finding the radius of a circular arch given its other dimensions. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.