All five congruence rules, the two cases that fail, and the isosceles results, on the chapter's hardest questions.
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Twelve cards covering every term and condition in the chapter.
The skills this chapter has built, drawn from the chapter summary.
The marked figure you need for the missing-angles question.
Identify the known angles and equal sides first, then use triangle properties to find the missing values.
Eight questions rising from recall to analysis across the whole chapter.
What is the defining characteristic of two congruent geometric figures?
Three exercise questions to answer in full sentences with reasons.
Focus on: the exact order of letters in the congruence statement.
Focus on: finding an included angle, stating the congruence condition, and using alternate interior angles.
Focus on: identifying the shared sides/angles of a square, and checking the vertex mapping for ΔCDA.
Work through the large marked figure and find every missing angle.
Refer to the large composite figure (Rectangle ACDB). The figure contains numerous intersecting triangles with known angles like 34°, 44°, 46°, 56°, 68°, 30°, 90°, and 98°. Segments with the same number of tick marks are equal in length.
Find the missing angles across the figure. State your answers and justify them.
List 3-4 specific missing angles you found.
Explain the rules you used: angle sum (180°), opposite equal sides, or congruent triangles.
Reason through when one triangle can be congruent to another in several ways.