Question 216618: question #6
find the slope of the line containing the points (-1,4)and (1,-3) Found 4 solutions by DRichardson, rfer, MathTherapy, Edwin McCravy:Answer by DRichardson(63) (Show Source):
There are two ways:
First way -- the graphical approach:
Plot the two points:
Draw the line between them
From the lower point, draw a line vertically upward
until the top of the line is exactly even with the
upper point, like the green line below:
Count the number of units the vertical green line is in
length by comparing it to the units on the y-axis. We
see that it is 7 units in length. So the numerator
of the slope is 7.
Next we draw a horizontal green line from the top of that
green vertical line over to the upper point, like this:
Count the number of units the horizontal green line is in
length by comparing it to the units on the x-axis. We
see that it is 2 units in length. Also the fact that the
horizontal line was drawn to the left, the denominator
of the slope is taken to be negative. So the denominator of
the slope is -2, so the slope is
or
Second way -- the formula approach:
Use the formula
where
and
Edwin