Answer:
the maximum is 450 and the minimum is 0.
Step-by-step explanation:
We know that:
P(x, y) = 25*x + 45*y
First, is easy to see that as x and y increase, also does the value of P(x, y)
So we just need to find the largest and smallest possible values of these variables. We also can notice that the variable y is being multiplicated by a larger coefficient than x, so we prioritize larger values of y when we can.
We know that:
4x+y ≤ 16
x + y ≤10
x≥0
y≥0
Let's start with the second inequality, let's solve this for y:
y ≤ 10 - x
and from the first one we get:
y ≤ 16 - 4*x
Just to show that maximizing x does not work, let's do it:
from the second one, knowing that the minimum value of y is y = 0
we have that:
0 ≤ 16 - 4*x
Here the maximum value that y can take is x = 1
0 ≤ 16 - 4*1 = 0
So we can have the combination y = 0 and x = 1, when we maximize x (here we can see that we should not maximize x)
in this case we get:
P(1, 0) = 25*1 + 47*0 = 25
let's write again our inequalities:
y ≤ 10 - x
y ≤ 16 - 4*x
If now we take the minimum value of x, x = 0, we get:
y ≤ 10
y ≤ 16
Because the first one is more restrictive, we know that the maximum value that y can take (when x = 0) is y = 10
in this case we get:
P(0, 10) = 25*0 + 45*10 = 450
As expected, here is the actual maximum for the given restrictions.
For the minimum, we just need to take the two lowest possible values of x and y, which are the two given by the equalities on:
x≥0
y≥0
The smallest values are:
x = 0
y = 0
Replacing that in the equation we get:
P(0, 0) = 25*0 + 47*0 = 0
So the maximum is 450 and the minimum is 0. (with the given restrictions)
