Algebra 1 Online!
Henrico County Public Schools, Virginia
Expressions and Operations

Equations and Inequalities



SOL Review Materials
The student will collect and analyze data, determine the equation of the curve of best fit in order to make predictions, and solve real-world problems, using mathematical models. Mathematical models will include linear and quadratic functions.
Essential Knowledge and Skills 
  • Write an equation for a curve of best fit, given a set of no more than twenty data points in a table, a graph, or real-world situation.
  • Make predictions about unknown outcomes, using the equation of the curve of best fit.
  • Design experiments and collect data to address specific, real-world questions.
  • Evaluate the reasonableness of a mathematical model of a real-world situation.
Essential Understandings
  • The graphing calculator can be used to determine the equation of a curve of best fit for a set of data.
  • The curve of best fit for the relationship among a set of data points can be used to make predictions where appropriate.
  • Many problems can be solved by using a mathematical model as an interpretation of a real-world situation.  The solution must then refer to the original real-world situation.
  • Considerations such as sample size, randomness, and bias should affect experimental design.
Vertical Articulation
  1. SOL 8.13 - a) make comparisons/predictions/ inferences, using information displayed in graphs; b) construct/analyze scatterplots
  2. SOL AFDA.3 - collect data/generate equation for the curve (linear/quadratic/exponential/log) of best fit/use best fit equations to interpolate function values/make decisions/justify conclusions (algebraic/graph models)
  3. SOL AII.9 - collect/analyze data/determine equations of the curve of best fit/make predictions/solve real world problems, using models (polynomial/exponential /log)
Instructional Materials
  1. VDOE ESS Lesson: Quadratic Curve of Best Fit - Statistics (PDF) - Determining a quadratic curve of best fit (Word)
  2. VDOE ESS Lesson: Line of Best Fit - Statistics (PDF) - Developing a curve of best fit for data (Word)
  3. VDOE ESS Lesson: How Much Is That Tune? - Statistics (PDF) - Solving systems of two linear equations in two variables (Word)
  4. VDOE ESS Lesson: Linear Curve of Best Fit - Statistics (PDF) - Determining a linear curve of best fit (Word)
  5. Notes: TI83 Best Fit Models (pdf)
  6. Notes: TI83 Curve Fitting with Residuals (pdf) 
Real World Lessons
  1. Dan Meyer: Will It Hit The Hoop: Will the ball go in the hoop?
  1. ExamView Quiz: Line of Best Fit
  2. Prentice Hall Quiz: Data Analysis
  3. Prentice Hall Quiz: Line of Best Fit
  1. Mathematics Assessment Project:
    • A07:Functions - Apprentice - You are given a set of points on a graph. Your task is to find one linear fuction and one quadratic function which, between them, pass through all the points.
    • A23:Scatter Diagram - Apprentice - In this task, you will use a scatter diagram to compare the results of two school tests. 
    • E11:Table Tiling - Expert - In this task, you must work out how many whole, half and quarter tiles tiles are needed to cover the tops of tables of different sizes.
  2. Six Tasks for Quadratics (pdf)
  1. Video: PH Making a Scatter Plot
  2. Video: PH Using Scatter Plots and Trend Lines to Make Predictions
  3. Video: PH Modeling Data Using a Linear, Quadratic, or Cubic Model *New 2009 SOL Content*
  4. Video: PH Writing an Equation for a Trend Line
  5. Video: PH Writing an Equation for a Line of Best Fit
  6. Video Tutor - Linear Models
Explore Learning
  1. Determining a Spring Constant - Place a pan on the end of a hanging spring. Measure how much the spring stretches when various masses are added to the pan. Create a graph of displacement vs. mass to determine the spring constant of the spring.
  2. Estimating Population Size - Adjust the number of fish in a lake to be tagged and the number of fish to be recaptured. Use the number of tagged fish in the catch to estimate the number of fish in the lake.
  3. Function Machines 2 (Functions, Tables, and Graphs) - Drop a number into a function machine, and see what number comes out! You can use one of the six pre-set function machines, or program your own function rule into one of the blank machines. Stack up to three function machines together. Input and output can be recorded in a table and on a graph.
  4. Quadratics in Factored Form - Investigate the factors of a quadratic through its graph and through its equation. Vary the roots of the quadratic and examine how the graph and the equation change in response.
  5. Real-Time Histogram - Try to click your mouse once every 2 seconds. The time interval between each click is recorded, as well as the error and percent error. Data can be displayed in a table, histogram, or scatter plot. Observe and measure the characteristics of the resulting distribution when large amounts of data are collected.
  6. Roots of a Quadratic - Find the root of a quadratic using its graph or the quadratic formula. Explore the graph of the roots and the point of symmetry in the complex plane. Compare the axis of symmetry and graph of the quadratic in the real plane.
  7. Slope-Intercept Form of a Line - Activity B - Compare the slope-intercept form of a linear equation to its graph. Vary the coefficients and explore how the graph changes in response.
  1. Interactive: Linear Regression Applet - plot up to 50 points and predict the line of best fit
  2. Interactive Notes: Line of Best Fit - lessons and practice problems at
  3. Notes: Using the TI Calculator to Find the Quadratic Function *New 2009 SOL Content*
Old Website Links
Common Core Standards