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Fuel Economy

Are hybrid cars worth the extra cost?

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Fuel Economy

Are hybrid cars worth the extra cost?

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Are hybrid cars worth the extra cost? Many vehicles are available with both standard gas-powered engines or hybrids. While the hybrid models require less gas and are better for the environment, they may initially cost thousands of dollars more.

In this lesson, students use linear equations to compare the costs of driving a car with a standard engine versus a hybrid engine and debate whether new buyers should always go green

REAL WORLD TAKEAWAYS

  • Hybrid cards use an electric motor at slower speeds which burns less fuel, causing less air pollution, than a gas powered one.
  • Hybrids cars typically cost more up front than their standard versions but require buying less gas to travel the same distance.
  • Which car is a better deal depends on how much one drives, how those miles are divided over the city and highway, and how long they plan to keep the car.

MATH OBJECTIVES

  • Write and solve equations to solve real-world questions
  • Compare proportional relationships represented in different forms including: tables, graphs, and equations

Appropriate most times as students are developing conceptual understanding.
Grade 8
Solving Linear Equations
Grade 8
Solving Linear Equations
Content Standards 8.EE.7 Solve linear equations in one variable. (a) Give examples of linear equations in one variable with one solution, infinitely many solutions, or no solutions. Show which of these possibilities is the case by successively transforming the given equation into simpler forms, until an equivalent equation of the form x = a, a = a, or a = b results (where a and b are different numbers). (b) Solve linear equations with rational number coefficients, including equations whose solutions require expanding expressions using the distributive property and collecting like terms. 8.F.4 Construct a function to model a linear relationship between two quantities. Determine the rate of change and initial value of the function from a description of a relationship or from two (x, y) values, including reading these from a table or from a graph. Interpret the rate of change and initial value of a linear function in terms of the situation it models, and in terms of its graph or a table of values.
Mathematical Practices MP.1 Make sense of problems and persevere in solving them. MP.2 Reason abstractly and quantitatively. MP.3 Construct viable arguments and critique the reasoning of others. MP.4 Model with mathematics. MP.6 Attend to precision. MP.8 Look for and express regularity in repeated reasoning.

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