Answer:
y = 15.75x + 25 is the linear equation
$88 would be the total cost
Step-by-step explanation:
First, create the equation using y = mx + b, where x is the number of hours:
y = 15.75x + 25 will be the equation, since the charge is $15.75 per hour and the flat fee is $25
There are 4 hours in between 8:30 AM and 12:30 PM, so to find the cost, plug in 4 as x and simplify:
y = 15.75x + 25
Plug in 4 as x:
y = 15.75(4) + 25
y = 63 + 25
y = 88
So, the total cost would be $88
For this case we have the following expression:

We follow the steps below:
We subtract 4x on both sides of the equation:

We subtract 10 from both sides of the equation:

Now, we must complete squares.
When we have an equation of the form:
, if we want to complete squares we must subtract c on both sides of the equation obtaining:

The square is completed by adding to both sides of the equation: 
So, we have left:

In the given expression we have:

And to complete the square we have:

Rewriting we have:

We factor the left side of the equation, that is, we look for two numbers that when added together result in -8 and when multiplied as a result 16. We have:

So, we have:

Answer:
The intermediate step is to complete squares

Mean is the average....so you add all the numbers and then divide by how many numbers there were.
12 + 13 + 15 + 28 + 28 +30 + 42 = 168
since there are 7 numbers, you divide 168 by 7.
168/7 = 24
Therefore, 24 is the mean.
The flag is Japan I believe.
Hope this helps!
Well lets do this
3 + 16 ÷ 4
we divide first
3 + 4
Addition
=7