Exercise 11 Page 188

Given a graph, can you think of two different ways to find the slope?

Description: See solution.
Slope: 46

Practice makes perfect

Observing the given graph, we can see that the line passes through the points (- 3,- 3) and (3,1). 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, or change in y, is 4. Similarly, the run, or change in x, is 6. slope=rise/run ⇔ m=4/6 We can confirm this answer by using the Slope Formula. m = y_2-y_1/x_2-x_1 We will use the given points to solve for the slope.

m = y_2-y_1/x_2-x_1

SubstitutePoints

Substitute ( - 3,- 3) & ( 3,1)

m=1-( - 3)/3-( -3)

SubNeg

a-(- b)=a+b

m=1+3/3+3

AddSubTerms

Add and subtract terms

m=4/6

We obtained the same number as before. We can be sure the slope is 46.