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

CBSE Class 12 Sample Paper for 2020 Boards
CBSE Class 12 Sample Paper for 2020 Boards
Last updated at Dec. 16, 2024 by Teachoo
Transcript
Question 13 If [■8(1&2@2&1)][■8(𝑥@𝑦)] = [■8(5@4)], then value of y is _______ [■8(1&2@2&1)][■8(𝑥@𝑦)] = [■8(5@4)] [■8(1×𝑥+2×𝑦@2×𝑥+1×𝑦)] = [■8(5@4)] [■8(𝑥+2𝑦@2𝑥+𝑦)] = [■8(5@4)] Therefore, x + 2y = 5 2x + y = 4 Now solving (1) and (2), Doing (2) – 2 × (1) (2x + y) – 2 × (x + 2y) = 4 – 2 × 5 2x + y – 2x – 4y = 4 – 10 y – 4y = –6 –3y = –6 y = (−6)/(−3) y = 2 So, value of y is 2