Answer:
[tex]-\frac{1}{8}[/tex]
Step-by-step explanation:
y=mx+b
m= slope (rise over run)
The slope of y=8x+5 is [tex]\frac{8}{1}[/tex]
When a line is perpendicular, the slope is the opposite reciprocal.
[tex]\frac{8}{1}[/tex] would be flipped to [tex]-\frac{1}{8}[/tex]
