16.2 Angles in parallel lines — Practise

1. Lines $l$ and $m$ are parallel. A corresponding angle is $72^\circ$. Find its pa

Answer: $72^\circ$

2. Lines $p$ and $q$ are parallel. An alternate angle is $118^\circ$. Find its part

Answer: $118^\circ$

3. Co-interior angles are $x^\circ$ and $67^\circ$. Find $x$.

Answer: $113^\circ$

4. Parallel lines are crossed by a transversal. One angle is $54^\circ$. Find the c

Answer: $126^\circ$

5. Corresponding angles are $(3x+8)^\circ$ and $(5x-26)^\circ$. Find $x$ and the an

Answer: $x=17$; each angle is $59^\circ$.

6. Co-interior angles are $(2x+15)^\circ$ and $(3x+10)^\circ$. Find $x$.

Answer: $x=31$

7. A corresponding angle is $73^\circ$. Find the adjacent angle on the same straigh

Answer: $107^\circ$; corresponding angles match, then angles on a line sum to $180^\circ$.

8. An alternate angle is $101^\circ$. Explain why its partner is also $101^\circ$.

Answer: They are equal because the lines are parallel and alternate angles are equal.