Answer:
<em>The domain of f is (-∞,4)</em>
Step-by-step explanation:
<u>Domain of a Function</u>
The domain of a function f is the set of all the values that the input variable can take so the function exists.
We are given the function

It's a rational function which denominator cannot be 0. In the denominator, there is a square root whose radicand cannot be negative, that is, 4-x must be positive or zero, but the previous restriction takes out 0 from the domain, thus:
4 - x > 0
Subtracting 4:
- x > -4
Multiplying by -1 and swapping the inequality sign:
x < 4
Thus the domain of f is (-∞,4)
Y= 18 because vertical angles are congruent.
Following PEMDAS is crucial to solving these. Please Excuse My Dear Aunt Sally
P - Parenthesis
E - Exponents
M - Multiplication
D - Division
A - Addition
S - Subtraction
Multiplication/Division and Addition/Subtraction are interchangeable.
Now then, number 1 has the following:

There are no parenthesis or exponents, but there is multiplication, so we will start with multiplying. There are two multiplication expressions in the problem.


Since you did that, your answer has been simplified to:

Now, all you have to do is combine your like terms. Since every term is alike, you can combine the whole expression.

So, your final answer would be:

Hopefully with this information, you can solve the rest. If you have any questions, let me know.
Answer:
(D)
x + (x + 2) + (x + 4) = 66