Chapter 9 - Quadratic Functions and Equations - 9-1 Quadratic Graphs and Their Properties - Practice and Problem-Solving Exercises - Page 539: 46

K

The basic form of the equation is $y=a(k(x-d))^{2} + c$ The a value in a equation determines the vertical stretch or compression. As the a value increases the graph is vertically stretched and becomes narrower. The graph of K has the highest a value and is vertically stretched and is narrower.