Data is rarely so uniform and predictable that plotting data points creates a perfectly linear arrangement. Scatter charts might have wildly varying plots that create a seemingly random correlation ...

Quadratic graph lines are U- or Ո-shaped, which is called a parabola. A linear graph can be drawn using only three points. A quadratic graph is a curve, so more points are plotted to support accuracy.

https://doi.org/10.4169/college.math.j.45.1.054 https://www.jstor.org/stable/10.4169/college.math.j.45.1.054 Summary We present a result of Rosenthal, which shows ...