Graphing a Quadratic Data Set Using Technology

8.12.1 Graphing a Quadratic Data Set Using Technology

8.12.1 • Graphing a Quadratic Data Set Using Technology

Warm Up

  1. Click on the "+" sign and choose to add a table in the Desmos graphing tool. This will generate a table for entering a data set.

Desmos: Quadratic Data Set Table

  1. Enter the data set shown in the table below into the corresponding x1x1 and y1y1 columns.

(If preferred, the data can be copied and pasted into Desmos from a spreadsheet using keyboard shortcuts. Windows: Ctrl+C for copy and Ctrl+V for paste. Mac: Command+C for copy and Command+V for paste.)

x1x1 y1y1
1 2
2 5
3 10
4 17
5 26

The window should be appropriately set to display the points in the table, but sometimes it will be necessary to adjust the window of the graph in order to properly view your data set. Use the mouse to drag and change the viewing window. To zoom in or out, use the buttons in the top right or the scrolling wheel on the mouse.

  1. Examine the data for a pattern that might fit any quadratic function that you recognize. What equation do you hypothesize would best fit these data points?

Compare your answer:

The data match the quadratic function y=x2+1y=x2+1.

In this lesson, we will learn to use technology to analyze a data set, find a curve of fit, and make predictions about a situation given the data that we have.

Why Should I Care?

A tablet screen displays the SAFE-RAIN logo with a fountain icon, above two photos of illuminated fountains at night in city settings. A hand is seen on the left side of the tablet.

Safe-Rain produces equipment for some pretty amazing fountains. Some of their fountains shoot jets of water that can form incredible visual displays and can be synchronized to music.

The path of a jet of water can be modeled with a quadratic function. When Safe-Rain designs a new fountain, they use quadratic functions to plan precisely how high and far each jet of water will go. Without quadratic equations to guide it, the water would spray everywhere.