Okay. So you know how ordered pairs are set up, right?
(x, y)
So, for example, take a look at the FIRST ordered pair: (15, 35)
In this case...
X = 15
Y = 35
You see?
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Now, we have two ordered pairs.
Here's the formula for finding the slope:
\[\frac{ y_{1}-y_{2} }{x_{1}-x_{2} }\]
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I'll walk you through this formula step by step.
1. Look at our ordered pairs.
(15, 35) and (195, 50)
2. Find the FIRST Y, and subtract the SECOND Y.
35 - 50 = -15
This is the NUMERATOR (top) of the slope fraction.
3. Find the FIRST X, and subtract the SECOND X.
15 - 195 = -180
This is the DENOMINATOR (bottom) of the slop fraction.
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So now we have the slope fraction!
\[\frac{ -15 }{ -180 }\]
which is the same as \[\frac{ 15 }{ 180 }\]