Tell whether the lines are "parallel", "perpendicular", or "neither."
-9x + 3y = 12 12x + 4y = 18
A) Perpendicular
B) Neither
C) Parallel

Question

Quizplus · Accepted Answer

The slopes of the two lines are equal, indicating they are parallel. To see this, rewrite each equation in slope-intercept form (y = mx + b). For the first equation, 3y = -9x + 12, or y = -3x + 4. For the second, 4y = -12x + 18, or y = -3x + 4.5. Since the slopes (-3) are equal and the y-intercepts are different, the lines are parallel.

Tell Whether the Lines Are "Parallel", "Perpendicular", or "Neither