Question

Which pair of lines in Fig. are parallel? Give reasons.

Answer 1

Correct option is A. $$AB\parallel CD, AD\parallel BC$$
$$\Rightarrow$$ $$\angle A+\angle D=115^o+65^o$$

$$\Rightarrow$$ $$\angle A+\angle D=180^o$$

$$\therefore$$ $$\angle A$$ and $$\angle D$$ are supplementary angles.

$$\therefore$$ $$AB\parallel CD$$

Now,

$$\Rightarrow$$ $$\angle A+\angle B=115^o+65^o$$

$$\Rightarrow$$ $$\angle A+\angle B=180^o$$

$$\therefore$$ $$\angle A$$ and $$\angle B$$ are supplementary angles.

$$\therefore$$ $$AD\parallel BC$$