Given two points m and n on the coordinate plane, find the slope of line mn, and state the slope of the line perpendicular to line mn: m(9,6) n(1,4)

The slope of the line MN where M (9,6) and N (1,4) can be obtained by obtaining the rate of the rise over the run. This is shown below:

(y2 - y1)/(x2 - x1) = (4 - 6)/(1 - 9) = (-2)/(-8)
m1 = 1/4

The slope of the line perpendicular to line MN can be obtained by taking the negative reciprocal of the slope of line MN.

m1 = 1/4
m2 = -1/m1 = -1/(1/4) = -4

Therefore, the slope of the line perpendicular to line MN is -4.

When two lines intersect, they form two pairs of equal angles, which, taking one of each, add up to 180°. (jargon: angles forming a straight line   show more