Respuesta :

m = y2-y1 / x2-x1
= 2-1 / 1-2
= 1 / -1
= -1

Answer:

slope = -1

Step-by-step explanation:

From the graph you can find the slope by starting at one point and count to the next point (rise over run).  -1/1 = 1

OR

use the slope formula m = (y2-y1)/(x2-x1) = (1-2)/(2-1) = -1