Area of a Rectangle: An Interactive Demonstration
This interactive demonstration explores how to calculate the area of a rectangle. It provides a hands-on way to understand and apply the well-known formula: Area = base × height. You can directly manipulate the shape on the canvas and instantly see how changes in its dimensions affect the final area calculation. ✨
Grab and drag the two corner markers to change the rectangle’s dimensions.
How to Use
Rectangle Tab ▭
This is the main tab for exploring the rectangle’s area.
- Reveal Buttons: Click the series of reveal buttons to walk through the calculation step-by-step: █ base, █ height, █ formula, █ substitute values, and the final █ area.
- Toggle Grid: The Grid button overlays a grid of unit squares on the rectangle, helping you visualize and count the area directly.
- Show Count: Once the grid is active, use the Show Count button to number the squares sequentially, making it easy to confirm that the count matches the calculated area.
Global Controls
These controls are always visible and affect the entire canvas.
- Tools: You can toggle the Ruler and Protractor to take manual measurements.
- Measurements: The Show Measurements button toggles the dimension callouts (base and height) on the shape.
- Randomize: Click the Randomize button to generate a new rectangle with different dimensions.
- Snap To: The Snap To dropdown changes how precisely you can drag the vertices, allowing you to snap to full, half, or quarter units for easy whole-number dimensions.
Settings Tab ⚙️
Customize the look of the canvas to your preference.
- Paper Style: Use the Paper Style dropdown to change the background from plain to grid lines or dots.
- Paper Color: Pick a new Paper Color for the background.
- Line/Dot Color: Change the color of the background pattern with the Line/Dot Color picker.
Related Activities
The concept of a rectangle’s area is the foundation for understanding the area of many other shapes. Explore these related demonstrations: