Answer:
The objective function is P(x,y) = 55x + 95y
P(600, 1400) is $166000
P(600, 1700) is $194500
P(1500, 1700) is $244000
P(1200, 800) is $142000
P(1500, 800) is $158500
They need to sell 1500 of the basic models  and 1700 of the advanced models to make the maximum profit
Step-by-step explanation:
Let us solve the question
⾠x denotes the number of  basic models
âľ y is the number of advanced models
âľ They will make $55 on each basic model
âľ They will make $95 on each advanced model
â The profit is the total amount of money-making on them
â´ Profit = 55(x) + 95(y)
â´ Profit = 55x + 95y
â´ The objective function is P(x,y) = 55x + 95y
Let us test the vertices on the objective function
âľ The vertices are (600, 1400), (600, 1700), (1500, 1700), (1200, 800),
  and (1500, 800)
â substitute each vertex in the objective function
âľ x = 600 and y = 1400
â´ P(600, 1400) = 55(600) + 95(1400) = 166000
â´ P(600, 1400) = $166000
âľ x = 600 and y = 1700
â´ P(600, 1700) = 55(600) + 95(1700) = 194500
â´ P(600, 1700) = $194500
âľ x = 1500 and y = 1700
â´ P(1500, 1700) = 55(1500) + 95(1700) = 244000
â´ P(1500, 1700) = $244000
âľ x = 1200 and y = 800
â´ P(1200, 800) = 55(1200) + 95(800) = 142000
â´ P(1200, 800) = $142000
âľ x = 1500 and y = 800
â´ P(1500, 800) = 55(1500) + 95(800) = 158500
â´ P(1500, 800) = $158500
âľ The greatest profit is $244000
â That means the maximum profit will be with vertex (1500, 1700)
ⴠThey need to sell 1500 of the basic models  and 1700 of the
  advanced models to make the maximum profit