Question

If `[(2, 0),(0, 4)][(x),(y)] = [(2),(-8)]`, the value of x and y respectively are ______.

Options

• 1, –2

• –2, 1

• 1, 2

• –2, –1

Answer 1

If `[(2, 0),(0, 4)][(x),(y)] = [(2),(-8)]`, the value of x and y respectively are 1, –2.

Explanation:

`[(2, 0),(0, 4)][(x),(y)] = [(2),(-8)]`

`[(2x + 0y),(0x + 4y)] = [(2),(-8)]`

`[(2x),(4y)] = [(2),(-8)]`

On equating the corresponding terms,

2x = 2

`\implies` x = 1

and 4y = – 8

`\implies` y = – 2

(1, –2)