line d passes through points (1,7) and (8,10).line e is perpendicular to d . what is the slope of line e

Question

Need help with this problem anyone 

Answer 1

The first thing you need to remember is perpendicular lines have negative reciprocal slopes.  This means opposite signs and flipped over.

 

 

The second thing you need to remember is how to find slope.  Slope equals change in y over change in x.

 

For line d the change in y is 3 since it goes from 7 to 10  and the change in x is 7 since it goes from 1 to 8.

 

Thus the slope for line d is 3/7.  If we flip 3/7 and change its sign we will have the slope for the perpendicular line e.

 

Thus the slope of line e is -7/3.