What are the values of x and y in the matrix subtraction below?

Question

asked Dec 12, 2021 235k views

2 Answers

Robin Roth · Answer 1 · 2021-12-18T20:28:05+0000

Answer:

Option x=-15 and y=15 is correct

Therefore the values are x=-15 and y=15

Explanation:

Let A and B be the given matrices

Let
$A=\left|\begin{array}{ccc}-20&4&9\\16&0&-6\end{array}\right|$

and
$B=\left|\begin{array}{ccc}-5&-6&0\\1&7&11\end{array}\right|$

To find the subtraction of the matrix A and B

$A-B=\left|\begin{array}{ccc}-20&4&9\\16&0&-6\end{array}\right|-\left|\begin{array}{ccc}-5&-6&0\\1&7&11\end{array}\right|$

$=\left|\begin{array}{ccc}-20+5&4+6&9-0\\16-&0-7&-6-11\end{array}\right|$

$=\left|\begin{array}{ccc}-15&10&9\\15&-7&-17\end{array}\right|$

Therefore
$A-B=\left|\begin{array}{ccc}-15&10&9\\15&-7&-17\end{array}\right|$

Therefore compare
$A-B=\left|\begin{array}{ccc}-15&10&9\\15&-7&-17\end{array}\right|$ =
$\left|\begin{array}{ccc}x&10&9\\y&-7&-17\end{array}\right|$

We get x=-15 and y=15

Therefore the values are x=-15 and y=15

Option x=-15 and y=15 is correct