Let's set up a system of equations to represent the situation:
Expense equation: y = 0.04x + 24
Revenue equation: y = 0.50x
The expense equation represents Lucas's total expenses, which includes $24 for materials and $0.04 for each ribbon sold. The revenue equation represents the total revenue from selling x ribbons at $0.50 per ribbon.
To find the number of ribbons Lucas needs to sell to break even, we need to set the revenue equation equal to the expense equation:
0.04x + 24 = 0.50x
Subtracting 0.04x from both sides, we get:
24 = 0.46x
Dividing both sides by 0.46, we get:
x = 52.17
Since Lucas cannot sell a fraction of a ribbon, he needs to sell at least 53 ribbons to break even.
So, Lucas needs to sell at least 53 ribbons to cover his expenses and break even.