Add 9 to both sides
So
33=2x
Divide both sides by 2
So
X=16.5
Given:
A company wants to select 1 project from a set of 4 possible projects.
Consider the options are:
a.
b.
c.
d. 
To find:
The constraints that ensures only 1 will be selected.
Solution:
It is given that the company wants to select 1 project from a set of 4 possible projects. It means the sum of selected projects must be equal to 1.

Therefore, the correct option is (a).
The last one since it contains only fractions
Total = 3^x, where x is the number of jobs worked.
Let x = 7th job:
Total = 3^7 = 2187 pennies. = $21.87
I might be wrong but:
x is less than negative three and x is greater than or equal to negative one.
Inequality is x<-3 and x ≥ -1