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Two brothers inherit land that they want to divide equally between them. The local land records indicate that the land is bounded roughly by the two functions:
86x2 and y=102x18, where x and y are measured in kilometers.
If they choose to put up a fence along a border running north and south, where should they put the fence?

  1. Enter the functions in F1(X) and F2(X)
  2. Use Plot or Numeric view to establish that the two boundaries intersect at x≈-9.8 and x≈7.2 Screen Right
  3. Use Signed Area to estimate the area of the land to be 188.37 km2 (18,837 hectares), so each brother should get approximately 94.185 km2

  4. Optional: use Signed Area to get a visual estimation of the boundary

  5. Define F3(X) as follows: F3(X)=9.8XF1(T)F2(T)δT Screen Right
  6. Use Plot view to get an estimate (x≈-0.7) and then use Numeric View to zoom in on the solution: x≈-0.644

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In this example, we used the Function app to easily visualize and estimate the solution to a typical classroom problem. In our next example, we extend that power of visualization.