Answer:
[tex]x\:<\:50[/tex].
Step-by-step explanation:
The z-score for a normal distribution is calculated using the formula:
[tex]Z=\frac{x-\mu}{\sigma}[/tex].
From the question, the distribution has a mean of 50.
[tex]\implies \mu=50[/tex] and the standard deviation is [tex]\sigma=5[/tex].
For a z-score to be negative, then, [tex]\frac{x-\mu}{\sigma}\:<\:0[/tex].
[tex]\frac{x-50}{5}\:<\:0[/tex].
[tex]x-50\:<\:0\times 5[/tex].
[tex]x-50\:<\:0[/tex].
[tex]x\:<\:0+50[/tex].
[tex]\therefore x\:<\:50[/tex].
Any value less than 50 will produce a negative z-score