In Fig. 5.18, a and b are
a. alternate exterior angles
b. corresponding angles
c. alternate interior angles
d. vertically opposite angles

Solution:

Given, the figure represents two lines m and n cut by a transversal l.

We need to find a and b.

Since,m and n are two lines cut by a transversal l,

When two parallel lines are crossed by a transversal, the pair of angles formed on the inner side of the parallel lines, but on the opposite sides of the transversal are called alternate interior angles.

We know that the alternate interior angles are equal.

So, ∠a = ∠b

The angles a and b are the interior angles that lie on the opposite sides of the transversal l.

Therefore, a and b are alternate interior angles.

✦ Try This: From the figure, find the value of ∠COD.

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

NCERT Exemplar Class 7 Maths Chapter 5 Problem 20

In Fig. 5.18, a and b are: a. alternate exterior angles, b. corresponding angles, c. alternate interior angles, d. vertically opposite angles

Summary:

In Fig. 5.18, a and b are alternate interior angles

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