1. 2.3 slope.notebook August 24, 2012
Slope = rise y2 ­ y1
= slope is brought to
run x2 ­ x1 you by the letter m
Vertical Horizontal
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2. 2.3 slope.notebook August 24, 2012
y ­ y
Use m = 2 1 to find the slope of lines containing the following points.
x2 ­ x1
( 8, 9) (12, 13) (5, 2) (­5, 2)
The line whose slope has the greater absolute value is steeper.
Which line is steeper?
Line 1: (­3, 0) and (1, 5)
Line 2: (­2, ­6) and (4, ­1)
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3. 2.3 slope.notebook August 24, 2012
The estimated number of cellular phone subscribers in the United States
was 13 million in 1993, 61 million in 1998, and 219 million in 2006.
Find the average yearly rate of change in the number of subscribers
(a)from 1993 to 1998 and (b) from 1998 to 2006.
327,577,529 in June 2011
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