Answer: There are 75 books.
Price of each book = $4.
Step-by-step explanation:
Let x = Number of books in the box.
Then as per given,
Cost of x books = $300
Cost of one book = 
Books left after giving 15 of them = x-15
Selling price of (x-15) books= $330
Selling price of one book = 
Profit on each book= $1.50
Profit = selling price - cost price
![\Rightarrow 1.50=\dfrac{330}{x-15}-\dfrac{300}{x}\\\\\Rightarrow\ 1.50=\dfrac{330(x)-300(x-15)}{x(x-15)}\\\\\Rightarrow\ 1.50=\dfrac{330x-300x+4500}{x^2-15x}\\\\\Rightarrow\ 1.50(x^2-15x)=30x+4500\\\\\Rightarrow\ 1.50x^2-22.5x=30x+4500\\\\\Rightarrow\ 1.50x^2-52.5x-4500=0\\\\\Rightarrow\ 1.50x^2-52.5x-4500=0\\\\\Rightarrow\ x^2-25x-3000=0\ \ [\text{divide by 1.5}]](https://tex.z-dn.net/?f=%5CRightarrow%201.50%3D%5Cdfrac%7B330%7D%7Bx-15%7D-%5Cdfrac%7B300%7D%7Bx%7D%5C%5C%5C%5C%5CRightarrow%5C%201.50%3D%5Cdfrac%7B330%28x%29-300%28x-15%29%7D%7Bx%28x-15%29%7D%5C%5C%5C%5C%5CRightarrow%5C%201.50%3D%5Cdfrac%7B330x-300x%2B4500%7D%7Bx%5E2-15x%7D%5C%5C%5C%5C%5CRightarrow%5C%201.50%28x%5E2-15x%29%3D30x%2B4500%5C%5C%5C%5C%5CRightarrow%5C%201.50x%5E2-22.5x%3D30x%2B4500%5C%5C%5C%5C%5CRightarrow%5C%201.50x%5E2-52.5x-4500%3D0%5C%5C%5C%5C%5CRightarrow%5C%201.50x%5E2-52.5x-4500%3D0%5C%5C%5C%5C%5CRightarrow%5C%20x%5E2-25x-3000%3D0%5C%20%5C%20%5B%5Ctext%7Bdivide%20by%201.5%7D%5D)
Number of books cannot be negative.
So, there are 75 books.
Price of each book = 
So price of each book = $4.
Answer:
7 + 4
Step-by-step explanation:
note that 
× = a
Given
(2 + )² = (2 + )(2 + )
Each term in the second factor is multiplied by each term in the first factor, that is
2(2 + ) + (2 + ) ← distribute both parenthesis
= 4 + 2 + 2 + 3 ← collect like terms
= 7 + 4
To find this out the easy way, add up all the numbers and an answer, then divide by 4.
59 + 64 + 68 + 63.67 = 254.67
254.67/4 = 63.66
A is not correct.
59 + 64 + 68 + 65.25 = 256.25
256.25/4 = 69.25
B is not quite correct.
59 + 64 + 68 + 75 = 266.
266/4 = 66.5
C is not correct.
59 + 64 + 68 + 89 = 280
280/4 = 70.
D.) is the correct answer.
I hope this helps!
Answer:
sorry
Step-by-step explanation:
sorry i dont know the answer because i read in class 2
i am very sorry
Answer:
x
=
4
or
x
=
−
4
Explanation:
First divide throughout by
2
to get
x
2
=
16
Now take the square root on both sides to get
x
=
±
4
.
You may now substitute the values of
x
=
4
and
x
=
−
4
back into the original equation and check that it satisfies the equation which it does.
Step-by-step explanation:
