Equations of Parallel and Perpendicular Lines

If two lines are parallel their slopes are  ____________

• the same.
• negative reciprocals of each other.

Are these lines parallel?
y = 12x + 4
y = 12x +14

• YES
• NO

Are these lines parallel?

y = (-1/2)x + 1

y = (1/2)x - 5

• YES

• NO

Write an equation of a line that passes through the point (5,-1) and is parallel to the line y = (-3/5)x -3

• y = (-3/5)x + 2
• y = (-3/5)x -2
• y = (3/5)x + 2
• y = (5/3) + 2

Write an equation of a line that passes through the point (2,6) and is parallel to the line y = -3

• y = 12
• y = 6
• x = 12
• x = 6

If two lines are perpendicular to each other their slopes are ____________

• the same.

• negative reciprocals of each other.

Are these lines perpendicular?
y = (1/2)x + 2
y = -2x + 13

• YES
• NO

Write an equation of a line that passes through the point (-9,2) and is perpendicular to the line y = 3x - 12

• y = (-1/3)x - 1
• y = (1/3)x - 2
• y = -3x + 12
• y = 3x - 1

Write an equation of a line that passes through the point (7,10) and is perpendicular to the line y = (1/2)x - 9

• y = -2x - 24
• y = -2x + 12
• y = -2x  + 24
• y = (1/2)x - 12

Are the lines parallel, perpendicular, or neither?
y = 3x – 7
y = 3x + 1

• Parallel
• Perpendicular 
• Neither