Which theorem should you use?

Use AAAA when two corresponding angles already match. Use SASSAS when two sides are proportional and the included angle matches.

Use SSSSSS when all three corresponding side ratios agree. The tool keeps the proof short so the theorem choice stays obvious.

Proof-writing reminder

  • Name the triangles in matching vertex order.
  • List only the facts needed for the chosen theorem.
  • State the theorem before writing the final similarity conclusion.

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