Answer: |50 - 4x| - 5 = 0
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Step-by-step explanation:
x = cost of one dinner
4x = cost of four dinners
50-4x = the difference in the cost of $50 vs 4x dollars
To ensure this difference is never negative, we use absolute value to form the expression |50-4x|
Set this equal to 5 since we want this distance or difference to be 5 units above or below 50
|50-4x| = 5
|50 - 4x| - 5 = 0