If a line joining two points goes down and to the right, the slope is

If a line joining two points goes down and to the right, the slope is

• A. Positive
• B. Zero
• C. Undefined
• D. Negative

Answer: (D)

Slope tells you how y changes as x increases. If the line goes down as you move to the right, the rise is negative while the run is positive, so the slope is negative. For example, with two points on such a line, (0,5) and (3,2) gives rise = 2−5 = −3 and run = 3−0 = 3, so slope = −3/3 = −1. So the slope is negative. A line that rises to the right has a positive slope, a horizontal line has zero slope, and a vertical line has undefined slope.

Slope tells you how y changes as x increases. If the line goes down as you move to the right, the rise is negative while the run is positive, so the slope is negative. For example, with two points on such a line, (0,5) and (3,2) gives rise = 2−5 = −3 and run = 3−0 = 3, so slope = −3/3 = −1. So the slope is negative. A line that rises to the right has a positive slope, a horizontal line has zero slope, and a vertical line has undefined slope.