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Find the maximum value of the objective function and the values of x and y for which it occurs. F=2x+y

3x+5y<=45 x>=0 and y>=0
2x+4y<=32

1 Answer

7 votes

Answer:

The maximum value of the objective function is 30 at (15, 0).

Explanation:

Given the objective function, F = 2x + y

and the following constraints:

3x + 5y ≤ 45

2x + 4y ≤ 32

x ≥ 0

y ≥ 0

You must first find the intercepts of the given constraints to plot the points on the graph, and find the feasible region.

3x + 5y = 45

3x + 5y - 3x = - 3x + 45

5y = -3x + 45


(5y)/(5) = (-3x + 45)/(5)

y = -3/5x + 9 (Slope-intercept form).

Solve for y-intercept by setting x = 0:

y = -3/5x + 9

y = -3/5(0) + 9

y = 9

y-intercept: (0, 9).

Solve for x-intercept by setting y = 0:

y = -3/5x + 9

0 = -3/5x + 9

0 - 9 = -3/5x + 9 - 9

- 9 = -3/5x

Multiply both sides by (-5/3) to isolate x:


(-(5)/(3)) - 9 = (-(5)/(3)) - (3)/(5)x

15 = x

x-intercept: (15, 0).

Next, transform 2x + 4y ≤ 32 into slope-intercept form, and solve for the y- and x-intercepts:

2x + 4y = 32

2x + 4y - 2x = - 2x + 32

4y = -2x + 32

Divide both sides by 4 to isolate y:


(4y)/(4) = (-2x + 32)/(4)

y = -1/2x + 8 (slope-intercept form)

Solve for y-intercept by setting x = 0:

y = -1/2x + 8

y = -1/2(0) + 8

y = 8

y-intercept: (0, 8).

Solve for x-intercept by setting y = 0:

y = -1/2x + 8

0 = -1/2x + 8

0 - 8 = -1/2x + 8 - 8

-8 = -1/2x

Divide both sides by -1/2 to solve for x:

-8 / -1/2 = (-1/2x)/ -1/2


(-8)/(- (1)/(2) ) = (-(1)/(2)x )/(-(1)/(2))

16 = x

x-intercept: (16, 0).

Now that you have the following points: (0, 9), (15, 0), (0, 8), and (16, 0), you can plot these on the graph and setup a feasible region. (Please see the attached screenshot for details.

The x-intercept, (16, 0) is not included because it is not within the feasible region.

You must also evaluate the objective function at each corner point to identify which is the maximum value.

Corner Point F = 2x + y

(0, 0) F = 2(0) + (0) = 0

(0, 8) F = 2(0) + (8) = 8

(0, 9) F = 2(0) + (9) = 9

(15, 0) F = 2(15) + (0) = 30

(10, 3) F = 2(10) + (3) = 23

Therefore, the maximum value of the objective function is 30 at (15, 0).

Find the maximum value of the objective function and the values of x and y for which-example-1
User Mwnsiri
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