3.3 Properties of Slopes
Have you ever stood at the top of a ski hill and
read the signs?Bunny RunMain StreetWipe OutTerminator
What do these signs tell you?
They are all descriptions of how steep (dangerous) each hill is.
This is all you need if all you are doing is snowboarding.
What if you were an engineer and you wanted to build a roller coaster
How would you describe the steepness of these rides?
Engineers have created a mathematical measure for the
steepness of a line
Slope: The measure of a line’s steepness
Rise
Run
Slope = Rise
Run
Therefore, the steeper the slope, the greater the number…
Find the slope of the horizontal line:
Slope = Rise
Run
= 0cm
10cm= 0
0cm
10cm
Parallel lines are straight and never meet, like tracks
Find the slopes of the parallel line segments:
(2,0)
(11,3)(1,2)
(10,5)
L1
L2
X
Y
(2,0)
(11,3)L1
X
Y
(1,2)
(10,5)
L2
X
Y
From this example, it can be stated that
The slopes of parallel lines are equal!
Pg 1241-3, [4,5]a,c6a,c,e8a, 910,11