Graphs of Quadratic Functions (Parabolas)
Section: Coordinate GeometryBank code: COG-GQFGRE frequency: MediumPro
1. Core Idea
The graph of y = ax^2 + bx + c is a parabola — a symmetric U-shaped curve.
Three things describe it completely:
- Direction: opens up if a > 0, down if a < 0.
- Vertex: the turning point — the minimum if it opens up, the maximum if it opens down.
- Roots (x-intercepts): where it crosses the x-axis, if it does.
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