Two or more independent functions (say f(x) and g(x)) can be combined to generate a new function (say g(x)) using any of the following approach.
And many more.
The approach or formula to use depends on the question.
In this case, the combined function is:
The savings function is given as
The allowance function is given as:
The new function that combined his savings and his allowances is calculated as:
Substitute values for s(x) and a(x)
Open bracket
Collect like terms
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