Answer: 
<u>Step-by-step explanation:</u>
(4, 1) & (2, -5)
First, find the slope (m) and then the perpendicular (opposite reciprocal) slope:

Next, find the midpoint of (4, 1) and (2, -5):

Lastly, input the perpendicular slope and the midpoint into the Point-Slope formula to find the equation of the line:

Percent of change will always be positive because the change is an absolute value. As we know, absolute value is always a positive value because you don't pay attention to the direction, only the distance is important.
When multiplying numbers, it doesn't matter which number is first or second.
The correct answer is: Commutative Property of Multiplication