For this case we have the following expression:

From here, we must clear the value of a.
We then have the following steps:
Place the terms that depend on a on the same side of the equation:

Do common factor "a":

Clear the value of "a" by dividing the factor within the parenthesis:

Answer:
The clear expression for "a" is given by:

We know that
Population density<span> is a measurement of population per unit area
</span>[population density]=population/area-----><span>7,112,688/426.25----> 16686.66
16686.66----------> 16687 person/square mile
the answer is
</span>16687 person/square mile
Answer:
No! The answer is not zero. There can be infinite solutions for this equation.
Hope it helps!
The answer is 15/6 (5+5+5)/6