Question

In figure, lines $$l$$ and $$m$$ intersect each other at a point. Which of the following is false?

Answer 1

Correct option is D. $$\angle a=\angle d$$

The two lines $$l$$ and $$m$$ shown in the figure forms $$4$$ angles, $$a,\ b,\ c\ and\ d$$.

$$\angle a$$ and $$\angle b$$ are vertically opposite angles.

Hence, $$\angle a=\angle b$$.

Similarly, $$\angle c$$ and $$\angle d$$ are also vertically opposite angles.

Hence, $$\angle d=\angle c$$.

Also, $$\angle a$$ and $$\angle d$$ form a linear pair.

Hence, $$\angle a+\angle d=180^o$$

Since $$\angle a+\angle d=180^o$$, $$\angle a$$ cannot be equal to $$\angle d$$, unless they are both right angles, which is not the case here.

Hence, option D is false here.