IX Mathematics Chapter 20, Sindh Board. New Mathematics Book. Unit 20 - Theory of Quadratic Equations - Class 10 - Sindh Board and Karachi Board. Exercise 20.4 Q1, 2. Lecturer: Shaheer Yousuf Khan Time Stamps: 0:33 = Question no. 1 14:02 = Question no. 2 #shaheeryk #yksir #esylearning #merit2excel