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Here are some tips for Determining Slope, which aligns with New York state standards:

Determining Slope

For this topic, you will need to know how to identify points on a graph.
To review the Ordered Pairs topic, see here.

The slope of a line (m) tells you how steep is the line. You can figure out the slope of a line when you know the coordinates of two points on the line.

 m = y2 - y1 x2 - x1 where (x1, y1) and (x2, y2) are two points on the line

A simple way to remember the formula is "rise over run" where rise is the change in y (or change in up and down) and run is the change in x (or change in left and right).

There are four types of slopes: positive, negative, zero, and undefined.

Positive slope:

Lines with positive slopes go up from left to right.

(5,5) and (0,1) are two points on the line.

 m = y2 - y1 x2 - x1 = 5 - 15 - 0 = 45

Negative slope:

Lines with negative slopes go down from left to right.

(0,0) and (4,-3) are two points on the line.

 m = y2 - y1 x2 - x1 = - 3 - 04 - 0 = - 34

Zero slope:

Lines with zero slopes are horizontal lines going left and right.

(-6,5) and (2,5) are two points on the line.

 m = y2 - y1 x2 - x1 = 5 - 5- 6 - 2 = 0- 8 = 0

Undefined slope:

Lines with undefined slopes are vertical lines going up and down.

(4,6) and (4,2) are two points on the line.

 m = y2 - y1 x2 - x1 = 6 - 24 - 4 = 40 = undefined

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