Answer :
Total cost = [tex](3x + 6y + 1z) + (2x+5z) = 5x + 6y + 6z[/tex]
x = Cost a unit of rose bushes
y = Cost a unit of geraniums
z = Cost a unit of hostas
x = Cost a unit of rose bushes
y = Cost a unit of geraniums
z = Cost a unit of hostas