Classify the pair of equations.
\[
\begin{array}{l}
y=\frac{5}{4} x+12 \\
y=-\frac{4}{5} x+11
\end{array}
\]
Parallel lines
Perpendicular lines
Neither

Step 1 ：Classify the pair of equations: \[y=\frac{5}{4} x+12\] and \[y=-\frac{4}{5} x+11\].

Step 2 ：The slopes of the lines can be used to determine whether the lines are parallel, perpendicular, or neither. If the slopes are equal, the lines are parallel. If the product of the slopes is -1, the lines are perpendicular. If neither of these conditions is met, the lines are neither parallel nor perpendicular.

Step 3 ：The slopes of the given lines are \(\frac{5}{4}\) and \(-\frac{4}{5}\).

Step 4 ：Calculate the product of the slopes: \(\frac{5}{4} \times -\frac{4}{5} = -1\).

Step 5 ：Since the product of the slopes is -1, the lines are perpendicular.

Step 6 ：Final Answer: The pair of equations are \(\boxed{\text{Perpendicular lines}}\).