# Slope of a line

• A line is the set of points forming a straight path on a plane.

• The slope of the line through the distinct points $P_1 (x_1,y_1)$ first term and $P_2(x_2,y_2)$ is:

$m=\displaystyle{\frac{y_2-y_1}{x_2-x_1}}$

• 1.  Find the slope between (-3, 2) and (3, 7).

2.  Find the slope between (-3, 6) and (5, 2).

3.  Find the slope between (5, 4) and (5, 2).

4.  Find the slope between (-3, 2) and (5, 2).

• The slope of the line measures the “steepness of the line”.
• The bigger the absolute value of the slope, the steeper the line is.
• Positive slope means “rising” line
• Negative slope means “falling” line
• Undefined slope means vertical line.
• Zero slope means horizontal line.
1. Tell whether the slope of the following are positive, negative, zero or undefined.

1. Red

b.  Blue

c.  Purple

d.  Green

2.  Determine the slope of the line given its graph

a.

b.

3.  Determine the slope of the line containing each given pair of points.

1. (2,3) and (5, -1)

b. (2,3) and (2, -1)

c.  (4,-1) and (-2, -1)