First option is the correct answer
Answer: 6x- 2
Explanation: 2 less means (- 2) a number times 6 can be written as 6x
Answer:

Step-by-step explanation:
Arithmetic sequence:
In an arithmetic sequence, the difference between consecutive terms is always the same, and is called common difference.
The nth term is given by the following equation:

In which
is the first term and d is the common difference.
First term is 9 common difference is -2
This means that 
So, the nth term is given by:



Answer: Option b

Step-by-step explanation:
Linear equations have the following form:

Where the exponents n, m, s and h are always 0 or 1
To know which equations are nonlinear, identify among the options given, those that have exponents other than 1 or 0
Note that in option b) the exponent of the variable x is
therefore the equation is nonlinear
Finally the answer is the option b