Answer:
7 girls can go in the first place, 6 in the second, etc.
7! ways is the number of ways to arrange the girls.
likewise the boys can be arranged in 7! ways
The total number of ways becomes 7! * 7!
7! * 7! = 25,401 600 ways
(X+4)(X-4) is the LCD because you just have to look at the denominators and see what factors or values are not already part of your LCD.
Answer:

Step-by-step explanation:
- Option A
tells us that: When we add 5 to a variable x, we get 20. As it has a unique value for x and is completely equal to it(i.e. 15), It is an equality.
- Option B
tells us that: A variable x equals to 5. Hence, as x is unique for 5 and is wholly equal to it, it's an equality too. - Option C
tells us that: A variable x isn't 5 but lesser than it. As we cannot equate it to 5, nor we are given the nature of the variable x, it is an Inequality. - Option D
is an expression; It can't be called an equation or an inequality unless we relate it with another expression.
1.= 6,391
2.=6,3910
3. = 6,39100
All you do is add the 0s at the end