Question

9. Is the line through points P(7, 3) and Q(11, 0) perpendicular to the line through points R(6, –3) and S(3, 1)? Explain.A)Yes; their slopes have product –1.B)Yes; their slopes are equal.C)No, their slopes are not opposite reciprocals.D)No; their slopes are not equal ?

Answer 1

C) No, their slopes are not opposite reciprocals.

Explanation:

First we find the slopes.

slope of PQ = (3 - 0)/(7 - 11) = 3/(-4) = -3/4

slope of RS = (-3 - 1)/(6 - 3) = -4/3

product of the slopes = (-3/4) * (-4/3) = 1

The slopes are reciprocals, but they are not opposite reciprocals, so the lines are not perpendicular.