at a bakery, one customer pays $5.67 for 3 bagels and 4 muffins. Another customer pays $6.70 for 5 bagels and 3 muffins. Let x be the cost (in dollars) of a bagel and let y be the cost (in dollars) of a muffin. Which system of equations represents the situation above?
A. x + y = 7
x + y = 8

B. y = 3x + 5.67
y = 5x + 6.7

C. 3x + 4y = 6.7
5x + 3y = 5.67

D. 3x + 4y = 5.67
5x + 3y = 6.7