The composite function
works like this:
- Take a number
as input - Evaluate h(x) = 3x. Let's call this output z.
- Evaluate g(x) = 1/(z+2)
So, if we substitute back z = 3x, the final output is 1/(3x+2). We know that the denominator of a fraction can't be zero, so we must impose

That is the wrong answer. I just took the and got it wrong the right answer is (-4,-1).
The expression that can be used is 3.14 (6x4+6^2)
The surface area is 188.4
To find how long it will take to fill the tank, you can use the idea that every 30 seconds will get you one gallon closer to being full.
This means to fill 50 gallons, you will need 50 groups of 30 seconds.
50 x 30 = 1500 seconds
1500/60 = 25 minutes.
It will take 25 minutes.
You could also think of it as filling 2 gallons every minute. It would take 25 of these.