Slope of two lines have to be equal for thenlines to be parallel. In your case the slopes are different:
for the first line the slope is m_{1} = 4 for the second one m_{2}=1/4 - not parallel. For the lines to be perpendicular these two slopes have to satisfy the following condition
m_{1}xm_{2} = -1
In your case m_{1}xm_{2} = 4x(1/4) = 1 - not perpendicular.