How do you evaluate: To evaluate an algebraic expression, you have to substitute a number for each variable and perform the arithmetic operations. In the example above, the variable x is equal to 6 since 6 + 6 = 12. If we know the value of our variables, we can replace the variables with their values and then evaluate the expression.
Answer:
Part 1) see the procedure
Part 2) 
Part 3) 
Part 4) The minimum number of months, that he needs to keep the website for site A to be less expensive than site B is 10 months
Step-by-step explanation:
Part 1) Define a variable for the situation.
Let
x ------> the number of months
y ----> the total cost monthly for website hosting
Part 2) Write an inequality that represents the situation.
we know that
Site A

Site B

The inequality that represent this situation is

Part 3) Solve the inequality to find out how many months he needs to keep the website for Site A to be less expensive than Site B

Subtract 4.95x both sides


Divide by 5 both sides


Rewrite

Part 4) describe how many months he needs to keep the website for Site A to be less expensive than Site B.
The minimum number of months, that he needs to keep the website for site A to be less expensive than site B is 10 months
The answer is digit sum method.
Digit sum method is method used to check the sum of sum numbers. If the sum of all of the digits of numbers is equal to the sum of all of the digits of the total sum, then the arithmetic process was correct.
We need to check the sum of <span>104+34+228+877:
</span>104 + 34 + 228 + 877 = 1243
Let's first summarize the digits of individual numbers:
104 *** 1 + 0 + 4 = 5
34 *** 3 + 4 = 7
228 *** 2 + 2 + 8 = 12 *** 1 + 2 = 3
877 *** 8 + 7 + 7 = 22 *** 2 + 2 = 4
Now, let's sum these sums:
5 + 7 + 3 + 4 = 19 *** 1 + 9 = 10 *** 1 + 0 = <u><em>1</em></u>
Then, let's summarize the digits of the total sum:
1243 *** 1 + 2 + 4 + 3 = 10 *** 1 + 0 = <u><em>1</em></u>
Since the sums of the digits on the both sides of equation is 1, than the arithmetic process was correct and the sum of <span>104 + 34 + 228 + 877 is really 1243.</span>