In the figure, which of the two lines are parallel and why?

1.	In the figure, which of the two lines are parallel and why?
Answer» In Fig. (i) sum of two interior angles 132° + 48° = 180° [∴ equal to 180°] Here, we see that the sum of two interior angles on the same side of n is 180°, then they are the parallel lines. In Fig. (ii), the sum of two interior angles 73° + 106° = 179° ≠ 180°. Here, we see that the sum of two interior angles on same side of r is not equal to 180°, then they are not the parallel lines.

Answer»

In Fig. (i) sum of two interior angles 132° + 48° = 180° [∴ equal to 180°]

Here, we see that the sum of two interior angles on the same side of n is 180°, then they are the parallel lines.

In Fig. (ii), the sum of two interior angles 73° + 106° = 179° ≠ 180°.

Here, we see that the sum of two interior angles on same side of r is not equal to 180°, then they are not the parallel lines.

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