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1.22 Congruence Criteria for Triangles - SAS

The SAS Triangle Congruence Theorem states that if 2 sides and their included angle of one triangle are congruent to 2 sides and their included angle of another triangle, then those triangles are congruent. The applet below uses transformational geometry to dynamically prove this very theorem. Interact with this applet below for a few minutes, then answer the questions that follow. As you do, feel free to move the BIG WHITE POINTS anywhere you'd like on the screen!

Q1:

What geometry transformations did you observe in the applet above?

Select all that apply
  • A
  • B
  • C
Check my answer (3)

What if we had the SAS criteria for two triangles that shared a side?

What if we had the SAS criteria for two triangles that shared a side?

Q2:

What geometry transformations did you observe in the diagram above?

Select all that apply
  • A
  • B
  • C
Check my answer (3)

What if we had the SAS criteria for two triangles that shared a vertex?

What if we had the SAS criteria for two triangles that shared a vertex?

Q2:

What geometry transformations did you observe in the diagram above?

Select all that apply
  • A
  • B
  • C
Check my answer (3)