Question

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

Answer 1

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

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

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

AB = C

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

Now compare corresponding elements:

4x = 4

x = `4/4`

x = 1

4 + y = x

y = 1 − 4

y = −3

Hence, x = 1 and y = −3