General Idea:
When simplifying a rational expression, we need to do the below steps:
(i) Factor the Denominator of each fraction
(ii) Identify the Least Common Denominator (It is the product of prime factors involved with its highest exponent)
(iii) Identify and rewrite the equivalent fraction with the desired LCD.
(iv) Once the denominator are same, Combine the numerator.
Applying the concept:
What is the difference x/x^2-16-3/x-4
I assume that you mean to type the expression 
Step 1: Factoring 
Step 2: Identifying the LCD, we get 
Step 3: Rewriting the second fraction by multiplying x+4 on both top and bottom of second fraction so that we get the LCD.
![\frac{x}{x^2-16}-\frac{3}{x-4}=\frac{x}{(x+4)(x-4)} -\frac{3*(x+4)}{(x-4)*(x+4)} Step 4: Combine like terms since the denominators are same[tex] \frac{x-3(x+4)}{(x+4)(x-4)} =\frac{x-3x-12}{(x+4)(x-4)}=\frac{-2x-12}{(x+4)(x-4)} =\frac{-2(x+6)}{(x+4)(x-4)}](https://tex.z-dn.net/?f=%20%5Cfrac%7Bx%7D%7Bx%5E2-16%7D-%5Cfrac%7B3%7D%7Bx-4%7D%3D%5Cfrac%7Bx%7D%7B%28x%2B4%29%28x-4%29%7D%20%20%20-%5Cfrac%7B3%2A%28x%2B4%29%7D%7B%28x-4%29%2A%28x%2B4%29%7D%20%3C%2Fp%3E%3Cp%3EStep%204%3A%20Combine%20like%20terms%20since%20the%20denominators%20are%20same%3C%2Fp%3E%3Cp%3E%5Btex%5D%20%5Cfrac%7Bx-3%28x%2B4%29%7D%7B%28x%2B4%29%28x-4%29%7D%20%3D%5Cfrac%7Bx-3x-12%7D%7B%28x%2B4%29%28x-4%29%7D%3D%5Cfrac%7B-2x-12%7D%7B%28x%2B4%29%28x-4%29%7D%20%3D%5Cfrac%7B-2%28x%2B6%29%7D%7B%28x%2B4%29%28x-4%29%7D%20%20)
Conclusion:
In factored form the simplified expression 
In expanded form the simplified expression 
Answer:
80
Step-by-step explanation:
80 shirts on sale, some basic divisoin/ multiplication.
Answer: There are 
ways of doing this
Hi!
To solve this problem we can think in term of binary numbers. Let's start with an example:
n=5, A = {1, 2 ,3}, B = {4,5}
We can think of A as 11100, number 1 meaning "this element is in A" and number 0 meaning "this element is not in A"
And we can think of B as 00011.
Thinking like this, the empty set is 00000, and [n] =11111 (this is the case A=empty set, B=[n])
This representation is a 5 digit binary number. There are 
of these numbers. Each one of this is a possible selection of A and B. But there are repetitions: 11100 is the same selection as 00011. So we have to divide by two. The total number of ways of selecting A and B is the 
.
This can be easily generalized to n bits.
Answer:the length of line segment AC is 14
Step-by-step explanation:
The diagram is shown in the attached photo
Since Angle A B C and B C A are congruent. It means that they are equal. An isosceles triangle is a triangle that has two equal sides and two equal base angles. Since Angle A B C and B C A are equal, it means that the triangle is an isosceles triangle. It also means that sides AC and AB are equal. The expression becomes
3x - 7 = 2x
3x - 2x = 7
x =7
To determine the length of line segment AC. We will substitute x = 7 into 3x - 7. It becomes
3×7 - 7 = 21 - 7 = 14
