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Lesson Materials

Congruence

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Objective

6.15 The student will determine congruence of segments, angles, and polygons by direct comparison, given their attributes. Examples of noncongruent and congruent figures will be included.

 Directions Close 
  1. ΔABC is congruent to ΔDEF.

  2. Move the "drag" point or points A, B or C to view how they interact.
 Directions 2 Close 
  1. Drag a corner of the left triangle to make an isoscles triangle. What do you notice about the measure of the angles on the two congruent sides?
  2. Drag a corner of the right triangle and make a right angle. What kind of angle are the two remaining angles? Will this always be true? Why?

 Hands-On Activities Close 

 Other Web Sites Close 
  1. More Congruent Triangles
  2. Even More Congruent Triangles
 Puzzles & Problems tangram Close 
From Math Forum: Prove or disprove if it is true that if two quadrilaterals have the same area and the same perimeter, they will always be congruent.(hint: Take a parallogram and cut it in half diagonally.)