In Fig. 5.57, PQ || RT. Find the value of a + b.

Solution:

Given, PQ || RT.

We need to find the value of a + b.

Considering PQ || RT with RQ as transversal,

If two parallel lines are intersected by a transversal, each pair of alternate interior angles are equal.

So, ∠TRQ = ∠RQP

From the figure,

b = 55°

If two parallel lines are intersected by a transversal, each pair of corresponding angles are equal.

So, ∠SRT = ∠SPQ

From the figure,

a = 45°

Now, a + b = 55°+ 45°

= 100°

Therefore, the value of a + b is 100°

✦ Try This: In the given figure, two parallel lines are cut by a transversal. Find the value of x.

☛ Also Check: NCERT Solutions for Class 7 Maths Chapter 5

NCERT Exemplar Class 7 Maths Chapter 5 Problem 104

In Fig. 5.57, PQ || RT. Find the value of a + b.

Summary:

In Fig. 5.57, PQ || RT. the value of a + b is 100°

☛ Related Questions:

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