Solutions of Question 9 and 10 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan.
Show that the system of equations $2 x-y+3 z=\alpha ; 3 x+y-5 z=\beta ;-5 x-5 y+21 z=\gamma$
is inconsistent if $\gamma \neq 2 \alpha-3 \beta$.
Solution.
By making use of matrix of order $2$ by $2$ and $3$ by $3$ encode and decode the following words:
a. PAKISTAN
b. ISLAMABAD
c. COLLEGE
Solution.