Telangana SCERT Solution Class IX (9) Math Chapter 4 Lines and Angles Exercise 4.2
(1)
Given,
x : y : z = 2 : 3 : 5
Let,
x = 2a
y = 3a
z = 5a
The angle of the full circle is 360o
Here,
∠ AOE = xo [Vertically opposite angles]
∠ BOD = zo [Vertically opposite angles]
∠ COF = yo [Vertically opposite angles]
∠AOE + ∠EOD + ∠BOD + ∠BOF + ∠COF + ∠AOC = 360O
Or, x + y + z + x + y + z = 360o
Or, 2x + 2y + 2z = 360o
Or, 2(2a) + 2(3a) + 2(5a) = 360o [putting the values of x,y,z]
Or, 4a + 6a + 10a = 360o
Or, 20a = 360o
Or, a = 360o/20
= 18o
X = 2 x a
= 2 x 18o
= 36o
Y = 3a
= 3 x 18o
= 54o
Z = 5a
= 5 x 18o
= 90o
Hope above 4.2 Exercise Solution will help you to complete each math problem in a better way.
In 2nd question (iii) bit, you given wrong answer. The correct answer is 20