#### Answer

When a signed number is divided by $0$, the result is undefined because there is no number than when multiplied to $0$ gives the signed number itself.

#### Work Step by Step

RECALL:
$8 \div 2 = 4$ because $4 \times 2 = 8$
When a signed number such as $8$ is divided by zero, the result is undefined.
This is because there is NO real number $a$ such that
$8 \div 0 = a \longrightarrow a \times 0 = 8$