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Geometry: Triangles Classroom ActivitiesDownload
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Special Segments in Triangles

Students will construct and explore medians, altitudes, angle bisectors, and perpendicular bisectors of triangles. They then drag the vertices to see where the intersections of the segments lie in relation to the triangle, and they measure distances to identify relationships.
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    TI-84 Plus C Silver Edition
  • TI-84 Plus Silver Edition
  • TI-84 series
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Triangle Sides & Angles

Students will explore side and angle relationships in a triangle. First, students will discover where the longest (and shortest) side is located relative to the largest (and smallest) angle. Then, students will explore the Isosceles Triangle Theorem and its converse. Finally, students will determine the number of acute, right, or obtuse angles that can exist in any one triangle.
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    TI-84 Plus C Silver Edition
  • TI-84 Plus Silver Edition
  • TI-84 series
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Exterior & Remote Interior Angles

Students investigate an exterior angle and its two remote interior angles.
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    TI-84 Plus C Silver Edition
  • TI-84 Plus Silver Edition
  • TI-84 series
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Angle Bisectors in a Triangle

Students explore the relationships between an angle bisector and segments in a triangle.
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    TI-84 Plus C Silver Edition
  • TI-84 Plus Silver Edition
  • TI-84 series
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Balancing Point

In this activity, students will explore the median and the centroid of a triangle.
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    TI-84 Plus C Silver Edition
  • TI-84 Plus Silver Edition
  • TI-84 series
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HangingWithTheIncenter_ActivityOverview

Hanging with the Incenter

In this activity, students will explore the perpendicular bisector theorem and discover that if a point is on the perpendicular bisector of a segment, then the point is equidistant from the endpoints.
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    TI-84 Plus C Silver Edition
  • TI-84 Plus Silver Edition
  • TI-84 series
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Interior & Exterior Angles of a Triangle

Students measure interior and exterior angles of a triangle and make conjectures about their relationships.
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    TI-84 Plus C Silver Edition
  • TI-84 Plus Silver Edition
  • TI-84 series
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PerpendicularBisector_1

Perpendicular Bisector

Students will explore the perpendicular bisector theorem and discover that if a point is on the perpendicular bisector of a segment, then the point is equidistant from the endpoints.
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    TI-84 Plus C Silver Edition
  • TI-84 Plus Silver Edition
  • TI-84 series
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7896_Step_3

Special Triangles

Students visualize the construction of special right triangles and find the ratios of the sides.
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    TI-84 Plus C Silver Edition
  • TI-84 Plus Silver Edition
  • TI-84 series
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The Hinge Theorems

Students explore the inequality relationships that arise when some of the triangle congruence conditions are in place but others are not.
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    TI-84 Plus C Silver Edition
  • TI-84 Plus Silver Edition
  • TI-84 series
Download9,180