Geometry of Linear Systems in 2D

šŸ’” Use mouse wheel to zoom • Drag to pan

About This Visualization

šŸ“ Row Picture (Lines)

When you click "Solve System", you see the row picture:

  • Each equation represents a line in 2D space
  • $2x + y = 8$ is line $L_1$
  • $4x - 3y = 6$ is line $L_2$
  • The solution is where the lines intersect

This is how we traditionally visualize linear systems.

šŸ“Š Column Picture (Vectors)

When you click "Show Linear Combination", you see the column picture:

  • The system becomes: $c_1 \mathbf{v_1} + c_2 \mathbf{v_2} = \mathbf{b}$
  • $\mathbf{v_1}$ and $\mathbf{v_2}$ are the column vectors
  • We find scalars $c_1, c_2$ that combine them to reach $\mathbf{b}$
  • The parallelogram shows the vector addition

This reveals the geometric structure of solutions.

šŸ”— How They Connect

The inputs are synchronized! For the system:

$$\begin{cases} 2x + y = 8 \\ 4x - 3y = 6 \end{cases}$$

Row form: Two equations, two unknowns

Column form:

$$x \begin{bmatrix} 2 \\ 4 \end{bmatrix} + y \begin{bmatrix} 1 \\ -3 \end{bmatrix} = \begin{bmatrix} 8 \\ 6 \end{bmatrix}$$

The column vectors are: $\mathbf{v_1} = \begin{bmatrix} 2 \\ 4 \end{bmatrix}$ and $\mathbf{v_2} = \begin{bmatrix} 1 \\ -3 \end{bmatrix}$

The solution $x=3, y=2$ becomes $c_1=3, c_2=2$ in the vector view!

✨ Change either the equations or vectors - the other updates automatically!

šŸŽÆ Try It!

  • Change the equations to see different line configurations
  • Modify $c_1, c_2$ to explore different linear combinations
  • Zoom and pan to examine the solution closely
  • Notice: parallel lines = no solution, coincident lines = infinite solutions

Vector Input

System of Equations