Answer:
Step-by-step explanation:
That'd be the Substitution Property. Substitute -2 for x in x + 8 = 6 and arrive at the true statement 6 = 6.
Answer:
Part A) see the explanation
Part B) 
Step-by-step explanation:
Part A)
we know that
A relationship between two variables, x, and C, represent a proportional variation if it can be expressed in the form
or 
Let
C ---> is the total cost (represent the output or dependent variable)
x ----> is the number of books (represent the input or independent variable)
In this problem
we have a proportional relationship between the variables x and C
Part B) we know that
The linear equation is given by

The constant of proportionality k is the same that the slope or unit rate of the linear equation
In this problem the constant k is given

so

For x=12 books
substitute in the equation and solve for C

In function notation

Answer:
9 or 6 owo
Step-by-step explanation:
uwu
Answer:
exact form 3/2 decimal form 1.5 mixed number form 1 1/2
Step-by-step explanation: