Exercise 8 Page 160

Parallel lines have the same slope but different y-intercepts. Perpendicular lines have slopes that are opposite reciprocals of one another.

Parallel Lines: c and d
Perpendicular Lines: b and c, b and d

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Parallel lines have the same slope but different y-intercepts. Perpendicular lines have slopes that are opposite reciprocals of one another. Therefore, to determine if the lines are parallel, perpendicular, or neither, we first need to find their individual slopes using the Slope Formula.

Line	Points	y_2-y_1/x_2-x_1	Slope
a	( - 2,3) & ( 2,2)	2- 3/2-( - 2)	-1/4
b	( - 3,0) & ( 3,- 2)	- 2- 0/3-( - 3)	-1/3
c	( 0,- 2) & ( 2,4)	4-( - 2)/2- 0	3
d	( - 2,0) & ( 0,6)	6- 0/0-( - 2)	3

Lines c and d have the same slope, but different y-intercepts. Therefore, they are parallel. Meanwhile, the slopes of lines b & c and b & d are opposite reciprocals, so they are perpendicular. The line a is neither parallel nor perpendicular to lines b, c, and d.

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