Question

19. Find the value of x in below figure if l || m.​

Answer 1

by linear pair

2x + x = 180

3x = 180

x = 60

2x = 2 × 60

= 120

Answer 2

Given:

A figure in which l || m.

To find:

The value of x.

Solution:

To solve this question, first of all, we should know that if two lines l and m are parallel then the sum of two adjacent angles made by them will be equal to 180°.

These adjacent angles are said to form a linear pair.

So,

as given, we have

l is parallel to m, then

from figure,

x and 2x form a linear pair

So,

$x + 2x = 180°$

$3x = 180°$

$x = \frac{180}{3}$

$x = 60°$

Hence, the value of x is 60°.