Exercise 8 Page 194

Observing the given graph, we can see that the line passes through the points (-1,-4) and (2,2). 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 ( -1,-4) & ( 2,2)

m=2-( -4)/2-( -1)

▼

Simplify right-hand side

SubNeg

a-(- b)=a+b

m=2+4/2+1

AddTerms

Add 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.