Inequality Addition Investigation: Adding/Subtracting the Same Number
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This interactive GeoGebra worksheet demonstrates what happens when the same number is added to or subtracted from both sides of an inequality. By dragging point P or using a slider, students observe how points A and B on a number line shift to AP and BP, while the inequality sign remains unchanged. The core mathematical concepts include properties of inequalities, number line representation, and the effect of uniform operations on ordered pairs. The construction uses the Point command to create key objects A, B, P, and derived points AP, BP, along with auxiliary points R, C, D for visual comparison. This resource is ideal for middle school algebra lessons on inequality properties, as well as for high school review. It encourages hands-on exploration, helping students discover the invariant nature of inequality direction under addition or subtraction, and reinforces the concept of equivalent transformations.
GeoGebra Commands & Parameters
Point(xAxis) → APoint(xAxis) → B
AI Drawing Prompt Reference
Draw a number line with two draggable points representing the values on each side of an inequality. Add a slider or a draggable point to represent the same number to be added or subtracted. When this number changes, the original two points shift along the number line by the same distance, creating two new corresponding points while preserving their left-right order. Above or below the number line, indicate the inequality direction with a symbol or text, and show the correspondence between original and shifted points, so that it is clear the inequality direction remains unchanged after adding or subtracting the same number.
The prompt above was compiled from the original drawing commands and is for reference only.