Exercise 3 Page 181

Consider the given coordinate plane. We want to know which of the lines on this coordinate plane are parallel.

We want to know which of the lines on this coordinate plane are parallel. Two lines are parallel if their slopes are identical. We have been given two points on each line, so we have enough information to calculate their slopes using the Slope Formula. m=y_2- y_1/x_2- x_1 Note that when choosing points to substitute for ( x_1, y_1) and ( x_2, y_2), it does not matter which points on the line we choose, since the result will be the same. Let's start with line a, which passes through ( -3, 1) and ( 0, 3).

The slope of line a is 23. We will use the same method to identify the slopes of lines b and c.

Now that we have identified the slope of each line, we can see that a and b have the same slope, so they are parallel.