Matrices — Class 12 Maths Solution

ncert exercise SA NCERT,Ex.3.2,Q.No.9,Page.81
Question

Find x and y, if $2\left[ {\begin{array}{cccccccccccccccccccc}1&3\\0&x\end{array}} \right] + \left[ {\begin{array}{cccccccccccccccccccc}y&0\\1&2\end{array}} \right] = \left[ {\begin{array}{cccccccccccccccccccc}5&6\\1&8\end{array}} \right]$

Step-by-step Solution

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We have, $2\left[ {\begin{array}{cccccccccccccccccccc}1&3\\0&x\end{array}} \right] + \left[ {\begin{array}{cccccccccccccccccccc}y&0\\1&2\end{array}} \right] = \left[ {\begin{array}{cccccccccccccccccccc}5&6\\1&8\end{array}} \right]$

$\Rightarrow$ $\left[ {\begin{array}{cccccccccccccccccccc}2&6\\0&{2x}\end{array}} \right] + \left[ {\begin{array}{cccccccccccccccccccc}y&0\\1&2\end{array}} \right] = \left[ {\begin{array}{cccccccccccccccccccc}5&6\\1&8\end{array}} \right]$

$\Rightarrow$ $\left[ {\begin{array}{cccccccccccccccccccc}{2 + y}&6\\1&{2x + 2}\end{array}} \right] = \left[ {\begin{array}{cccccccccccccccccccc}5&6\\1&8\end{array}} \right]$

$\Rightarrow$ 2 + y = 5 and 2x + 2 = 8

$\Rightarrow$ y = 3 and x = 3

Hence, x = 3 and y = 3.

NCERT & Exemplar solution for CBSE Class 12 Mathematics, Matrices. Curated by Sachin Sharma. Free for all students.