Answer:
the unknown number c must be greater than 5.4286 in order for the inequality to be true. We can write this in interval notation as (5.4286, ∞).
Explanation:
The inequality can be written as:
7c - 8 > 30
To solve for c, we can first add 8 to both sides:
7c > 38
Then, we can divide both sides by 7:
c > 38/7
So the solution is:
c > 5.4286
Therefore, the unknown number c must be greater than 5.4286 in order for the inequality to be true. We can write this in interval notation as (5.4286, ∞).