Answer: f(4) = 21
Step-by-step explanation:
2(4)^2-11
4^2 = 16
2(16)-11
Multiply 2 and 16
32 - 11
Subtract
21
Answer: it’s d
Step-by-step explanation: i did that
Answer: A)There are 5 nonfiction books for every 9 fiction books in the library.
Step-by-step explanation: If you do the math you realize that there are clearly less nonfiction books than fiction books.
105/5=21 and after 21*9 lines up and to check your work than
5*21=105 and 9*21=189 it is not B because the smaller number 105 is in front of the ratio 105:189 and 5:9
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.
Follow these steps:
-8.4b - 4.2 = 12.6
Add 4.2 on both sides:
-8.4b = 16.8
Divide by -8.4 on both sides to give you the final answer of:
b = -2
So you're answer is indeed correct! Hope this helps and that the steps are clear enough!