8*(n+6)=80
distribute
8n+48 = 80
subtract 48 from each side
8n = 32
divide by 8
n=4
The constant rate of proportionality is 12!
12 because 6+6=12 or 6 times 2 = 12
The option formatting isn't very clear, anyway: given a number x, negative 3 times that number is -3x. If this has to be at least 57, it means that -3x must be greater than or equal to 57:

Dividing both sides by -3 solves the equation, but we have to switch the inequality sign because we're dividing by a negative number:
