Perpendicular Line Calculator

Category: Algebra and General

Find the equation of a line perpendicular to a given line that passes through a specific point.

What is a Perpendicular Line Calculator?

A Perpendicular Line Calculator helps you determine the equation of a line that is perpendicular to a given line and passes through a specified point. This is especially useful in mathematics, geometry, and physics when analyzing angles, slopes, and intersections between lines.

The calculator simplifies the process of finding the slope of the perpendicular line and determining its y-intercept based on the provided slope-intercept form equation and point coordinates.

How to Use the Perpendicular Line Calculator

  1. Input the Line Equation
  2. Enter the equation of the line in the form ( y = mx + b ), where:
    • ( m ) is the slope of the line.
    • ( b ) is the y-intercept.
  3. Example: ( y = 2x + 3 )

  4. Input the Point

  5. Enter the coordinates of a point through which the perpendicular line will pass.
  6. Format: ( (x, y) ).
  7. Example: ( 1, 2 ).

  8. Choose an Example (Optional)

  9. Use the dropdown menu to load pre-configured examples for quick calculations.

  10. Calculate

  11. Click the Calculate button to generate:

    • The slope of the perpendicular line.
    • The equation of the perpendicular line.
    • A step-by-step explanation of the solution.
    • A graph showing both the original line and the perpendicular line.
  12. Clear

  13. Use the Clear button to reset all inputs and outputs.

Step-by-Step Explanation Provided by the Calculator

The calculator breaks down the calculation process into the following steps:

  • Step 1: Determine the slope (( m )) of the original line.
  • Step 2: Compute the slope of the perpendicular line using the formula: [ m_{\text{perpendicular}} = -\frac{1}{m_{\text{original}}} ]
  • Step 3: Substitute the point (( x, y )) into the slope-intercept form: [ y = mx + b ] to calculate the y-intercept (( b )).
  • Step 4: Write the final equation of the perpendicular line.

Features of the Perpendicular Line Calculator

  • Graphical Representation
    The calculator plots both the original line and the perpendicular line on a graph, with the specified point highlighted.

  • Step-by-Step Solution
    A detailed explanation of the calculations, including intermediate steps and formulas used.

  • Handles Edge Cases
    The calculator processes equations with explicit and implicit slopes, such as:

  • ( y = 2x + 3 )
  • ( y = -x + 2 )
  • ( y = 4x - 5 )

Frequently Asked Questions (FAQ)

What is a perpendicular line?

A perpendicular line is a line that intersects another line at a ( 90^\circ ) angle. The slopes of perpendicular lines are negative reciprocals of each other.

How does the calculator handle vertical or horizontal lines?

  • If the original line is vertical (( x = c )), the perpendicular line will be horizontal (( y = b )) and vice versa.
  • The calculator identifies these special cases and provides the correct results.

What happens if I enter invalid input?

The calculator validates your input and displays an error message if the line equation or point format is incorrect. Ensure the equation is in the form ( y = mx + b ) and the point is in the format ( x, y ).

Can I see the graph of the calculated lines?

Yes! The graph shows the original line, the perpendicular line, and the specified point. The lines are color-coded for clarity.

Why is the slope of a perpendicular line the negative reciprocal?

The relationship between two perpendicular lines ensures their slopes (( m_1 ) and ( m_2 )) satisfy the condition: [ m_1 \cdot m_2 = -1 ] This condition guarantees that the lines intersect at a ( 90^\circ ) angle.

Why Use This Calculator?

This calculator provides a quick, accurate, and detailed solution for finding perpendicular lines. Whether you're a student, teacher, or professional, it simplifies complex calculations while enhancing understanding with its step-by-step explanation and visual graphing capabilities.