given the equation y = 3/4x - 6. Write TWO equations of lines in slope-intercept form that are PERPENDICULAR to the given line, y - 3/4x - 6. Then EXPLAIN how you know the equations you chose are perpendicular.

1 answer

To find two equations of lines that are perpendicular to the given line \( y = \frac{3}{4}x - 6 \), we first need to identify the slope of the original line. The slope (\( m \)) of the given line is \( \frac{3}{4} \).

When two lines are perpendicular, the product of their slopes is \(-1\). This means that if one line has a slope \( m_1 \), the slope \( m_2 \) of a line that is perpendicular to it can be found using the relation:

\[ m_1 \times m_2 = -1 \]

In our case, we have:

\[ m_1 = \frac{3}{4} \]

To find \( m_2 \):

\[ \frac{3}{4} \times m_2 = -1 \]

Solving for \( m_2 \):

\[ m_2 = -\frac{4}{3} \]

Now that we have the slope of a line that is perpendicular to the given line, we can write two equations with this slope. For simplicity, let's choose different \( y \)-intercepts:

Equation 1

Let’s take a \( y \)-intercept of \( 2 \): \[ y = -\frac{4}{3}x + 2 \]

Equation 2

Let’s take a \( y \)-intercept of \( -4 \): \[ y = -\frac{4}{3}x - 4 \]

Summary of the Two Perpendicular Lines

  1. \( y = -\frac{4}{3}x + 2 \)
  2. \( y = -\frac{4}{3}x - 4 \)

Explanation of Perpendicularity

Both lines have a slope of \( -\frac{4}{3} \), which is the negative reciprocal of the slope \( \frac{3}{4} \) of the original line. Since the product of the slopes of the original line and the new lines is:

\[ \frac{3}{4} \times -\frac{4}{3} = -1 \]

This confirms that the two new lines are indeed perpendicular to the original line.