Answer:
There are total 30 books in the 5 feet high stack of books.
Step-by-step explanation:
The complete question is
Given, Each note book is 2 inches thick, How many notebooks do you think it would take to make a stack that is 5 feet high
Solution
Thickness of each book 
The total height of the book stack is
feet.
The number of books in the stack is equal to total height of the stack divided by the thickness of one book
Number of books in five feet high stack is

Hence, there are total 30 books in the 5 feet high stack of books.
Answer:
The commutative property of multiplication states that changing the order of the numbers we are multiplying, does not change the product.
You would first make the fractions improper (making the numerator bigger then the denominator) in order to do that times the denominator with the whole number and add the numerator.
Ex) 3*8 = 24 + 5 = 29/8
Then you would add both of the improper fractions
Answer:
1) B) 10
2) B) 9
Step-by-step explanation:
1) 10x+15=115
10x=100
x=10
2) 12x+17=125
12x=108
x=9
<span>Simplifying
4x2 + -24x + 4y2 + 72y = 76
Reorder the terms:
-24x + 4x2 + 72y + 4y2 = 76
Solving
-24x + 4x2 + 72y + 4y2 = 76
Solving for variable 'x'.
Reorder the terms:
-76 + -24x + 4x2 + 72y + 4y2 = 76 + -76
Combine like terms: 76 + -76 = 0
-76 + -24x + 4x2 + 72y + 4y2 = 0
Factor out the Greatest Common Factor (GCF), '4'.
4(-19 + -6x + x2 + 18y + y2) = 0
Ignore the factor 4.
</span><span>Subproblem 1
Set the factor '(-19 + -6x + x2 + 18y + y2)' equal to zero and attempt to solve:
Simplifying
-19 + -6x + x2 + 18y + y2 = 0
Solving
-19 + -6x + x2 + 18y + y2 = 0
The solution to this equation could not be determined.
This subproblem is being ignored because a solution could not be determined.
The solution to this equation could not be determined.</span>