In Fig. 6.7, AB, CD and EF are three lines concurrent at O. Find the value of y

Solution:

Given, AB, CD and EF are three lines concurrent at O.

We have to find the value of y.

We know that the vertically opposite angles are equal.

∠AOE = ∠BOF

So, ∠BOF = 5y

From the figure,

∠COE + ∠AOE + ∠AOD = 180°

2y + 5y + 2y = 180°

4y + 5y = 180°

9y = 180°

y = 180°/9

y = 20°

Therefore, the value of y is 20°.

✦ Try This: In the figure, l∣∣m and p∣∣q. Find the value of ∠x,∠y,∠w,∠u and ∠z

☛ Also Check: NCERT Solutions for Class 9 Maths Chapter 6

NCERT Exemplar Class 9 Maths Exercise 6.3 Sample Problem 1

In Fig. 6.7, AB, CD and EF are three lines concurrent at O. Find the value of y

Summary:

Concurrent lines are the lines which intersect each other exactly at one point. Concurrent lines are non-parallel lines and extend indefinitely in both directions. In Fig. 6.7, AB, CD and EF are three lines concurrent at O. The value of y is 20°

☛ Related Questions:

• In Fig.6.8, x = y and a = b. Prove that l || n
• In Fig. 6.9, OD is the bisector of ∠AOC, OE is the bisector of ∠BOC and OD ⊥ OE. Show that the point . . . .
• In Fig. 6.10, ∠1 = 60° and ∠6 = 120°. Show that the lines m and n are parallel