The total cost of the mortgage would be $264,192 or C.
We know that the area of a circle in terms of π will be πr². However the area with respect to the diameter will be a different story. The first step here is to find a function relating the area and diameter of any circle --- ( 1 )
For any circle the diameter is 2 times the radius,
d = 2r
Therefore r = d / 2, which gives us the following formula through substitution.
A = π(d / 2)² = πd² / 4
<u>Hence the area of a circle as the function of it's diameter is A = πd² / 4. You can also say f(d) = πd² / 4.</u>
Now we can substitute " d " as 4, solving for the area ( A ) or f(4) --- ( 2 )
f(4) = π(4)² / 4 = 16π / 4 = 4π - <u>This makes the area of circle present with a diameter of 4 inches, 4π.</u>
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


Read more about functions at:
brainly.com/question/15458447