8. For natural numbers $x, y$, $(x, y)$ is called a pair. It is stipulated that the pair $(x, y)$ is the same as $(y, x)$. If two pairs satisfy the following condition: the sum of the two numbers in one pair equals the product of the two numbers in the other pair, then these two pairs are called "companion pairs". Except for the pair $(2,2)$ and $(2,2)$, the "companion pairs" are
$\begin{array}{l}8 .(2,3) \text { and } \\ (1,5)\end{array}$