Find the slopes of the lines containing the following. (If an answer is undefined, enter UNDEFINED.) a) (3, −4) and (5, 6) b) (1, −1) and (6, −6) c) (0, c) and (d, 0)

Question

Find the slopes of the lines containing the following. (If an answer is undefined, enter UNDEFINED.)

a) (3, −4) and (5, 6)

b) (1, −1) and (6, −6)

c) (0, c) and (d, 0)

Answer 1

I would suggest you draw these points on a graph. First draw the points (3,-4) and (5,6), followed by the line that contains them. Then do the same for the points (5,6) and (1,-1). This will give you a better understanding of the concept of the slope. For the last case, the answer depends of course on the values of c and d. Try various cases for c 0, positive or negative, and d 0 positive or negative. Then the answer will become clear.

Answer 2

For two points (x1,y1) and (x2,y2) the slope of a line is (y2 - y1)/(x2 -x1). The slope is undefined in the denominator is zero, i.e., if both points have the same x-coordinate.