Quadrilateral klmn is a rectangle. the coordinates of l are l(1,-4) and the coordinates of m are m(3,-2) find the slopes of sides kl, lm, mn, and nk

We can start by finding the gradient of LM


Two perpendicular lines will meet the requirement ×=-1
Two parallel lines have equal gradients

NM is perpendicular to LM, hence the gradient of NM is -1
KN is a line that is parallel to NM, hence the gradient is 1
KL is perpendicular to LM, hence the gradient of KL is -1

The answer is 30 minutes to an hour