Question

what is the slope of 1,2.5 and -1,-2.5

Answer 1

5/2

Answer 2

-2.5-2.5/-1-1=5/2

Answer 3

\[\frac{\frac{25}{10}-\left(-\frac{25}{10}\right)}{1-(-1)}=\frac{5}{2} \]

Answer 4

The slope is the difference in the y values divided by the difference in the x values (you have to keep them in the same order!):

\[m = \frac{y_2-y_1}{x_2-x_1}\]
In your case, \[m=\frac{2.5-(-2.5)}{1-(-1)} = \frac{5}{2}\]

Answer 5

It also works to do them in the other order:
\[m=\frac{-2.5-2.5}{-1-1}=\frac{-5}{-2} = \frac{5}{2}\]

Answer 6

You just can't use the x values in one order, and the y values in the other:
\[m=\frac{-2.5-2.5}{1-(-1)}=\frac{-5}{2}\]which is incorrect.