Let x = number of tulips y = amount of daffodils We have the following system of equations: x + y = 15 5x + 2y = 45 Solving the system Step 1: -5x + -5y = -75 5x + 2y = 45 Step 2: -3y = -30 y = 30/3 = 10 Step 3: x = 15-y x = 15-10 x = 5 Answer: she should use 10 daffodils 5 tulips