Which graph best represents a parabola?

Which graph best represents a parabola?

• A. A straight line.
• B. A U-shaped parabola.
• C. A circle.
• D. A S-shaped cubic.

Answer: (B)

A parabola is the graph of a quadratic function, and it forms a smooth U-shaped curve when a ≠ 0. It is symmetric about a vertical line, and it can open upward or downward depending on the sign of the leading coefficient. The U-shaped graph matches this idea, showing the single curved arc that characterizes a parabola. A straight line is a linear function and has no bend. A circle isn’t a single-valued function of x over its entire domain and also doesn’t have the U-shaped form. An S-shaped cubic has a different curvature pattern and an inflection, so it isn’t a parabola.

A parabola is the graph of a quadratic function, and it forms a smooth U-shaped curve when a ≠ 0. It is symmetric about a vertical line, and it can open upward or downward depending on the sign of the leading coefficient. The U-shaped graph matches this idea, showing the single curved arc that characterizes a parabola.

A straight line is a linear function and has no bend. A circle isn’t a single-valued function of x over its entire domain and also doesn’t have the U-shaped form. An S-shaped cubic has a different curvature pattern and an inflection, so it isn’t a parabola.