Question

Class 9 Lines and angles theorem 6.7 of ncert maths book

Answer 1

Step-by-step explanation:

Given _ pqr

To prove - angle 1 +angle 2+angle3=180°

Const- ab line through p and ab || qr

Proof - angle 2= angle 4

angle 3=angle 5 (alternate interior angles)

angle 4+angle 1+angle 5=180°(inear pair)

angle 2+angle 1+angle 3 =180°

angle 1+angle 2 +angle 3=180°