Exercise 2 Page 77

We can use the given table of values to graph the data on a coordinate plane. Then we can find the slope of the line that connects the points.

One way to use a graph to find the slope of a line is to count the change in the x -coordinates and the change in the y-coordinates.

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

slope = y_2 - y_1/x_2-x_1

SubstitutePoints

Substitute ( 1,3) & ( 3,9)

slope=9- 3/3- 1

SubTerms

Subtract terms

slope=6/2

CalcQuot

Calculate quotient

slope=3

We obtained the same number as before. We can be sure the slope is 3. Now we can explain what the slope represents. A slope of 3 tells us that there are 3 feet in every yard.