Triangles

Topics in this chapter

• Triangle Definitions and Properties
• Triangle Angle Theorems
• Triangle Inequalities and Side-Angle Relations
• Isosceles Triangle Properties
• Triangle Congruence Criteria
• CPCT and Congruence Proofs
• Triangle Geometric Constructions

Cheat sheet

Practice questions

1. Question 1Q-A910CE

   If $\triangle ABC \cong \triangle PQR$, then which of the following is not true?

   1. A.$BC = QR$
   2. B.$\angle B = \angle Q$
   3. C.$CA = PR$
   4. D.$AB = QR$
   See the answer and solution
2. Question 2Q-F93B87

   In triangles $ABC$ and $PQR$, $AB = QR$, $\angle B = \angle P$, and $BC = PR$. Then:

   1. A.$\triangle ABC \cong \triangle PQR$
   2. B.$\triangle ABC \cong \triangle QRP$
   3. C.$\triangle ABC \cong \triangle RPQ$
   4. D.$\triangle ABC \cong \triangle PRQ$
   See the answer and solution
3. Question 3Q-681636

   In a triangle $ABC$, if $AB = AC$ and $\angle B = 50^\circ$, then the measure of $\angle A$ is:

   1. A.$50^\circ$
   2. B.$80^\circ$
   3. C.$100^\circ$
   4. D.$60^\circ$
   See the answer and solution
4. Question 4Q-59798A

   Which of the following is not a criterion for congruence of triangles?

   1. A.SAS
   2. B.SSA
   3. C.ASA
   4. D.SSS
   See the answer and solution
5. Question 5Q-DE3231

   If the vertical angle of an isosceles triangle is $70^\circ$, then each of its base angles is:

   1. A.$55^\circ$
   2. B.$70^\circ$
   3. C.$110^\circ$
   4. D.$50^\circ$
   See the answer and solution