Check sibling questions
Class 12
Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

If [1 2 2 1]Β  [xΒ  y] = [5 4] , then value of y is _______

If [1 2 2 1]Β  [xΒ  y] = [5 4] , then value of y is __ - Sample Paper

Question 13 - CBSE Class 12 Sample Paper for 2020 Boards - Part 2


Transcript

Question 13 If [β– 8(1&2@2&1)][β– 8(π‘₯@𝑦)] = [β– 8(5@4)], then value of y is _______ [β– 8(1&2@2&1)][β– 8(π‘₯@𝑦)] = [β– 8(5@4)] [β– 8(1Γ—π‘₯+2×𝑦@2Γ—π‘₯+1×𝑦)] = [β– 8(5@4)] [β– 8(π‘₯+2𝑦@2π‘₯+𝑦)] = [β– 8(5@4)] Therefore, x + 2y = 5 2x + y = 4 Now solving (1) and (2), Doing (2) – 2 Γ— (1) (2x + y) – 2 Γ— (x + 2y) = 4 – 2 Γ— 5 2x + y – 2x – 4y = 4 – 10 y – 4y = –6 –3y = –6 y = (βˆ’6)/(βˆ’3) y = 2 So, value of y is 2

Davneet Singh's photo - Teacher, Engineer, Marketer

Made by

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths and Science at Teachoo.