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Section2.3Apply It 2

The \(x\)- and \(y\)-intercepts of an applied function model almost always tell us something meaningful and interesting. Finding them is a snap once we have a model equation, using what we know from precalculus:

  1. To find a \(y\)-intercept, set \(x\) equal to zero and solve for \(y\text{.}\) That is, compute the value of \(y=f(0)\text{.}\) (This usually requires only arithmetic and no algebra.)
  2. To find a \(x\)-intercept, set \(y\) equal to zero and solve for \(x\text{.}\) This often requires considerably more algebraic technique, and is sometimes not feasible without technology.

Here's how that plays out with Decision Report 2's demand function: