Answer:
-9 or negative 9
Step-by-step explanation:
The opposite of negative 9 is positive 9.
The opposite of <em>that</em> is negative 9.
An inequality can be formed by simply translating the problem statement to numerical expressions.
From the problem we know that

added with

hours should be equal or greater than

(helpful insight from the keyword "at least"). Therefore, it's inequality would look like:

(>= is used instead of ≥ for constraints in formatting)
The inequality above best models the situation.
Answer:
a. 4/21
b. 4/7
Step-by-step explanation:
Please kindly check the attached files for explanation.