Exercise 2 Page 193

Observing the given graph, we can see that the line passes through the points (2,5) and (5,-1). One way to use a graph to find the slope of a line is to count out the change in x and y.

We can see that as the graph travels from left to right, the rise (change in y) is -6. Similarly, the run (change in x) is 3. slope=rise/run ⇔ m=-6/3=- 2 We can confirm this answer by using the Slope Formula. m = y_2-y_1/x_2-x_1 Let's use the given points to solve for the slope.

m = y_2-y_1/x_2-x_1

SubstitutePoints

Substitute ( 2,5) & ( 5,-1)

m=-1- 5/5- 2

SubTerms

Subtract terms

m=-6/3

CalcQuot

Calculate quotient

m=-2

Given that we obtained the same number as before, we can be sure the slope is -2.