Page 185 - Mathematics GRADE 9, DE-STREAMED (MTH1W)

• Fold along two diameters, each of which shares an endpoint with one of the chords, to find the centre of the circle, as shown below:
• Measure angle BAC (the inscribed angle) and angle BOC (the central angle), and state what you notice about their angle measures:
3. Provide students with a set of instructions that enable them to demonstrate their understanding of a circle property. For example:
• Step 1. For any circle, draw a chord.
• Step 2. Draw a segment from the midpoint of the chord to the centre of the circle.
• Step 3. Measure the angles formed by the segment and the chord.
• Step 4. Repeat with three different chords.
What appears to be true about the angles that are formed each time?
4. Have students fold paper to create geometric designs involving:
• finding the centre of a circle
• creating an equilateral triangle from a circle
• creating a hexagon from a rectangle and from a circle.
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