Here are the answers for 10 and 12
<h3>
Answer: y = (3/4)x + 13/4</h3>
This is the same as writing y = 0.75x + 3.25
slope is 3/4 = 0.75
y intercept is 13/4 = 3.25
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Explanation:
One marked point on this line is (-3,1)
Another point is at (1,4)
Let's find the slope of the line through these two points.
m = (y2-y1)/(x2-x1)
m = (4-1)/(1-(-3))
m = (4-1)/(1+3)
m = 3/4
m = 0.75
Now let's use point slope form to find the equation of the line
y - y1 = m(x - x1)
y - 1 = 0.75(x - (-3))
y - 1 = 0.75(x + 3)
y - 1 = 0.75x + 2.25
y = 0.75x + 2.25 + 1
y = 0.75x + 3.25
If you wanted, you can convert those decimal values to fraction form
- 0.75 = 75/100 = 3/4
- 3.25 = 325/100 = 13/4
That means the equation
y = 0.75x + 3.25
is the same as
y = (3/4)x + 13/4
The points you found are the vertices of the feasible region. I agree with the first three points you got. However, the last point should be (25/11, 35/11). This point is at the of the intersection of the two lines 8x-y = 15 and 3x+y = 10
So the four vertex points are:
(1,9)
(1,7)
(3,9)
(25/11, 35/11)
Plug each of those points, one at a time, into the objective function z = 7x+2y. The goal is to find the largest value of z
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Plug in (x,y) = (1,9)
z = 7x+2y
z = 7(1)+2(9)
z = 7+18
z = 25
We'll use this value later.
So let's call it A. Let A = 25
Plug in (x,y) = (1,7)
z = 7x+2y
z = 7(1)+2(7)
z = 7+14
z = 21
Call this value B = 21 so we can refer to it later
Plug in (x,y) = (3,9)
z = 7x+2y
z = 7(3)+2(9)
z = 21+18
z = 39
Let C = 39 so we can use it later
Finally, plug in (x,y) = (25/11, 35/11)
z = 7x+2y
z = 7(25/11)+2(35/11)
z = 175/11 + 70/11
z = 245/11
z = 22.2727 which is approximate
Let D = 22.2727
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In summary, we found
A = 25
B = 21
C = 39
D = 22.2727
The value C = 39 is the largest of the four results. This value corresponded to (x,y) = (3,9)
Therefore the max value of z is z = 39 and it happens when (x,y) = (3,9)
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Final Answer: 39
