Question

A = `[(x, 0),(1, 1)]`, B = `[(4, 0),(y, 1)]` and C = `[(4, 0),(x, 1)]`. Find the values of x and y, if AB = C.

Answer 1

Given A = `[(x, 0),(1, 1)]`, B = `[(4, 0),(y, 1)]`, C = `[(4, 0),(x, 1)]`

Now, AB = C

`[(x, 0),(1, 1)] [(4, 0),(y, 1)] = [(4, 0),(x, 1)]`

`\implies [(4x, 0),(4 + y, 1)] = [(4, 0),(x, 1)]`

Then, by equality of matrix

∴ 4x = 4

⇒ x = 1

And 4 + y = x

⇒ 4 + y = 1

y = – 3

Hence, x = 1 and y = – 3.