Given
Sunflower seed = s
Millet = m
Sold in 5-pound bags, this can be expressed as s + m = 5
Next,
Sold sunflower seed = $1.75 per pound
Sold millet = $2.50 per pound
The mixture is sold for $11.60, this is expressed as 1.75s + 2.50m = 11.60
Therefore, the system of equations is as follows:

Answer:
s + m = 5
1.75s + 2.5m = 11.60