CPM Homework Banner

Home > PC > Chapter 8 > Lesson 8.1.3 > Problem 8-45


Let  be the surface area of a cube with edge length .  

  1. Write as a function of

    A cube has six square sides of length . What is the area of each square?

  2. If  is the length of the longest diagonal of the cube, write an equation for as a function of

    Draw a triangle within the cube with the longest diagonal .

    Write an equation for the diagonal of the bottom square .

    Write an equation for the longest diagonal, .

  3. Write as a function of .

    Solve for in your equation from part (a) above. Then substitute that expression for into your equation.

Use the eTool below to solve this problem.
Click the link at right for the full version of the eTool: 8-45 HW eTool