Chapter 7: Triangles

Questions

1. $\angle P = 60^\circ, \angle Q = 40^\circ$: find $\angle R$.
2. State SAS rule.
3. Sides $3, 4, 8$: can they form a triangle?
4. State RHS congruence rule.
5. Each angle of an equilateral triangle?
6. In $\triangle ABC, AB = AC$, $\angle B = 65^\circ$: $\angle A$?
7. Prove: angles opposite equal sides are equal.
8. Sides $5$ and $9$: range of third side.
9. AB = AC, $\angle A = 40^\circ$: $\angle B$?
10. In a triangle, if one angle is $100^\circ$ and another $50^\circ$, is it possible?

Extra Practice (Optional)

• State ASA rule.
• In right $\triangle ABC$ with $\angle B = 90^\circ, AB = BC$: find $\angle A$.
• Sum of angles $A + B + C$ of any triangle.
• Congruence of two equilateral triangles with same side.
• Can sides $6, 8, 15$ form a triangle?