Determine if the sign is parallel perpendicular or neither

Y = -1/4 x
Y = 4x - 5

1 answer

To determine if the lines given by the equations \( y = -\frac{1}{4}x \) and \( y = 4x - 5 \) are parallel, perpendicular, or neither, we need to look at their slopes.

  1. Finding the slope of the first line \( y = -\frac{1}{4}x \):

    • The slope \( m_1 \) of this line is \(-\frac{1}{4}\).
  2. Finding the slope of the second line \( y = 4x - 5 \):

    • The slope \( m_2 \) of this line is \(4\).
  3. Comparison of the slopes:

    • Two lines are parallel if their slopes are equal, i.e., \( m_1 = m_2 \).
    • Two lines are perpendicular if the product of their slopes is \(-1\), i.e., \( m_1 \cdot m_2 = -1\).

Now, let's check:

  • The slopes are \( m_1 = -\frac{1}{4} \) and \( m_2 = 4 \).

Calculating the product of the slopes: \[ m_1 \cdot m_2 = -\frac{1}{4} \cdot 4 = -1 \]

Since the product of the slopes is \(-1\), the lines are perpendicular.

Conclusion: The lines \( y = -\frac{1}{4}x \) and \( y = 4x - 5 \) are perpendicular.