STEP 1: Recall what are parallel lines and what are perpendicular lines from earlier classes.
https://www.mathsisfun.com/perpendicular-parallel.html
STEP 2: Write if the lines are parallel or perpendicular to each other
Two lines are parallel to each other if the slopes of the two lines are equal to each other
Two lines are perpendicular to one another if the product of both the slopes m_{1}.m_{2} is equal to -1, where m_{1} is the slope of the first line and m_{2} is the slope of the second line.
Multiplying the given slopes \frac{4}{5}\times\frac{-4}{5} = -1
So, the given lines are perpendicular to one another.
Further skills you may want to recall:
What is the slope of a line
https://www.qalaxia.com/viewDiscussion?messageId=5d410ba5794a8b3151565d2d
How to multiply two fractions
