Skip to ContentGo to accessibility pageKeyboard shortcuts menu
OpenStax Logo
Algebra 1

8.12.5 Practice

Algebra 18.12.5 Practice
Search for key terms or text.

Access the Desmos guide PDF for tips on solving problems with the Desmos graphing calculator.

Complete the following questions to practice the skills you have learned in this lesson.

  1. Enter the given data into Desmos, then calculate the regression approximation to determine the curve of best fit.
    x 1 y 1
    2 56
    5 116
    8 155
    11 205
    17 230

What is the equation for the curve of best fit that models the data?

  1. 𝑦 = − 0.93 𝑥 2 + 22.63 𝑥 + 10.48
  2. 𝑦 = − 0.69 𝑥 2 + 24.83 𝑥 + 8.07
  3. 𝑦 = − 3.11 𝑥 2 + 16.32 𝑥 + 8.94
  4. 𝑦 = − 0.7 𝑥 2 + 35.93 𝑥 + 8.19
  1. Enter the given data into Desmos, then calculate the regression approximation to determine the curve of best fit.
    x 1 y 1
    3 105
    9 250
    14 349
    23 400
    37 258

What is the equation for the curve of best fit that models the data?

  1. y = − 0.74 x 2 + 34.32 x + 7.44
  2. y = − 0.62 x 2 + 17.45 x + 9.64
  3. y = − 2.31 x 2 + 24.711 x + 3.25
  4. y = − 0.56 x 2 + 38.74 x + 5.31
Access multimedia content
  1. Enter the given data into Desmos, then calculate the regression approximation to determine the curve of best fit.
    x 1 y 1
    0.2 6.5
    0.35 6.74
    0.66 6.31
    1 4.95
    1.5 1.2

What is the equation for the curve of best fit that models the data?

  1. y = − 5.1 x 2 + 9.2 x + 7.14
  2. y = − 4.31 x 2 + 3.2 x + 6.08
  3. y = − 3.1 x 2 + 2.6 x + 7.93
  4. y = − 6.3 x 2 + 8 x + 10.6
Access multimedia content
  1. Enter the given data into Desmos, then calculate the regression approximation to determine the curve of best fit.
    x 1 y 1
    0.3 25
    0.6 36
    1.2 45
    1.8 33
    2.3 12

What is the equation for the curve of best fit that models the data?

  1. y = − 35.78 x 2 + 45.21 x + 3.74
  2. y = − 3.72 x 2 + 7.34 x + 8.67
  3. y = − 30.84 x 2 + 49.61 x + 8.99
  4. y = − 25.41 x 2 + 59.28 x + 9.64
Access multimedia content

For questions 5 – 9, use the following information.

The path of a toy rocket after launch is modeled by the following data set. The height of the rocket, in feet, y , corresponds to the number of seconds passed, x .

  1. What is the equation for the curve of best fit that models the flight of the toy rocket?
  1. y = − 9.2 x 2 + 46 x + 3.51
  2. y = − 4.2 x 2 + 34 x + 6.34
  3. y = − 11.9 x 2 + 30.2 x + 3.64
  4. y = − 6.1 x 2 + 31 x + 1.24
Access multimedia content
  1. Approximately how high will the rocket be 2 seconds after launch?
  1. 61.00 feet
  2. 58.71 feet
  3. 53.60 feet
  4. 45.91 feet
  1. At what approximate times after launch will the rocket have a height of 20 feet?
  1. 0.82 seconds after launch and 4.18 seconds after launch
  2. 0.52 seconds after launch and 4.48 seconds after launch
  3. 0.39 seconds after launch and 4.61 seconds after launch
  4. 0.26 seconds after launch and 4.74 seconds after launch
  1. Approximately how long will it take the rocket to reach its maximum height?
  1. 5.08 seconds
  2. 3.20 seconds
  3. 2.50 seconds
  4. 1.73 seconds
  1. Approximately how long will it take for the rocket to land on the ground?
  1. 6.12 seconds
  2. 5.08 seconds
  3. 4.63 seconds
  4. 2.50 seconds

For question 10, Maria has found a curve of best fit using the equation below.


  1. Maria is asked to predict the y -value on her curve when x = 10 . To do this, she graphs the function x = 10 and analyzes the intersection point of the curve and the line.

What is the y -value Maria is asked to predict?

  1. 111
  2. 105
  3. 93
  4. 10
Access multimedia content
Access multimedia content
PreviousNext
Citation/Attribution

This book may not be used in the training of large language models or otherwise be ingested into large language models or generative AI offerings without OpenStax's permission.

Want to cite, share, or modify this book? This book uses the Creative Commons Attribution-NonCommercial-ShareAlike License and you must attribute OpenStax.

Attribution information
  • If you are redistributing all or part of this book in a print format, then you must include on every physical page the following attribution:

    Access for free at https://openstax.org/books/algebra-1/pages/about-this-course

  • If you are redistributing all or part of this book in a digital format, then you must include on every digital page view the following attribution:

    Access for free at https://openstax.org/books/algebra-1/pages/about-this-course

Citation information

© May 21, 2025 OpenStax. Textbook content produced by OpenStax is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike License . The OpenStax name, OpenStax logo, OpenStax book covers, OpenStax CNX name, and OpenStax CNX logo are not subject to the Creative Commons license and may not be reproduced without the prior and express written consent of Rice University.