Answer
$a.$
A line parallel to the given line has slope $m=-8.$
$b.$
A line perpendicular to the given line has slope $m=\displaystyle \frac{1}{8}$
Work Step by Step
If two nonvertical lines are parallel, then they have the same slope.
If two nonvertical lines are perpendicular, then the product of their slopes is -1.
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Reading the slope from $y=mx+b$
$ 8x+y=11 \qquad$ ... solve for y
$y= -8x+11 \quad$ The given line has slope $m=-8$.
$-8\displaystyle \cdot(\frac{1}{8})=-1$
$a.$
A line parallel to the given line has slope $m=-8.$
$b.$
A line perpendicular to the given line has slope $m=\displaystyle \frac{1}{8}$
