Line g is shown on the graph.

coordinate plane with line g that passes through the points negative 3 comma 2 and 0 comma 5

What is the equation of the line in slope-intercept form that is perpendicular to line g and passes through the point (4, 2)? Show all necessary steps.

1 answer

To find the equation of a line that is perpendicular to line \( g \) and passes through the point \( (4, 2) \), we will follow these steps:

  1. Find the slope of line \( g \).
  2. Determine the slope of the perpendicular line.
  3. Use the slope-point form to write the equation.
  4. Convert to slope-intercept form \( y = mx + b \).

Step 1: Find the slope of line \( g \)

The points that line \( g \) passes through are \( (-3, 2) \) and \( (0, 5) \). We can calculate the slope \( m \) using the formula:

\[ m = \frac{y_2 - y_1}{x_2 - x_1} \]

Assigning the coordinates, we have:

  • \( (x_1, y_1) = (-3, 2) \)
  • \( (x_2, y_2) = (0, 5) \)

Now substituting the values into the formula:

\[ m = \frac{5 - 2}{0 - (-3)} = \frac{3}{3} = 1 \]

So, the slope of line \( g \) is \( 1 \).

Step 2: Determine the slope of the perpendicular line

The slope of a line that is perpendicular to another line is the negative reciprocal of the slope of the original line. Therefore, if the slope of line \( g \) is \( 1 \), the slope of the perpendicular line is:

\[ m_{perpendicular} = -\frac{1}{1} = -1 \]

Step 3: Use the slope-point form to write the equation

Now we will use the point-slope form of the equation of a line, which is given by:

\[ y - y_1 = m(x - x_1) \]

Substituting \( m = -1 \) and the point \( (4, 2) \) (where \( x_1 = 4 \) and \( y_1 = 2 \)):

\[ y - 2 = -1(x - 4) \]

Step 4: Simplify to slope-intercept form

Now simplifying the equation:

\[ y - 2 = -1x + 4 \]

Adding \( 2 \) to both sides:

\[ y = -x + 6 \]

Thus, the equation of the line that is perpendicular to line \( g \) and passes through the point \( (4, 2) \) in slope-intercept form is:

\[ \boxed{y = -x + 6} \]