Solving equations
Carpenter's problem

As her first carpentering project, Lisa decided to build a trunk with a square base and a height of 50 centimeters (so that it fits under her bed).
The cost of wood is $4 per square meter. Lisa must figure out the dimensions of the trunk that she can built, considering her $8 budget. And she still hasn't decided whether her trunk will have a lid.


What will be the dimensions of the trunk?

Construct equations the solutions to which will help Lisa determine the dimensions of the trunk she can build, with and without a lid.

  • Find the solutions of the equations:
    Using a graphic representation. -
    Using a value table. -
    Transforming the equation into one of the [vertex form]=[constant] type and using the methods developed in the Equations of the type [vertex-form]=[constant] task.

    -
  • What will be the volume of the trunk with and without a lid?

  • Compare the various solutions you obtained using the methods listed above, as well as the solution you can obtain using the dynamic figure below (for a trunk without a lid).

  • How will the results you obtained change if Lisa decides that the base of the trunk will have a rectangular shape, with one side twice as long as the other?


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    The difference equation

    vertex form = constant
    quadratic function = constant
    The difference equation
    Carpenter's problem
    Playing fields
    Warm-up
    Table designs
    Isosceles triangles
    Cutting circles
    Pairs of numbers

    Exercise 1
    Exercise 2
    Exercise 3
    Exercise 4
    Exercise 5
    Exercise 6
    Exercise 7