Answer: first option
Step-by-step explanation:
The volume of a regular pyramid can be calculated with the following fromula:
Where B is the area of the base of the pyramid and h iis the height of the pyramid.
The base is a square, therefore, its area B is:
You know that the height is 3, therefore, you can substitute these values into the formula.
THerefore, the volume of the pyramid is:
I'm assuming all of (x^2+9) is in the denominator. If that assumption is correct, then,
One possible answer is
Another possible answer is
There are many ways to do this. The idea is that when we have f( g(x) ), we basically replace every x in f(x) with g(x)
So in the first example above, we would have
In that third step, g(x) was replaced with x^2+9 since g(x) = x^2+9.
Similar steps will happen with the second example as well (when g(x) = x^2)