Question

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

Answer 1

A

Explanation:

E2020

Answer 2

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