A and b are the minutes spent on machine A and machine B, respectively.
a+b = 40
b = 40-a
8a + 6b = 300
8a + 6(40-a) = 300
8a + 240 - 6a = 300
2a = 60
a = 30
b = 40-a = 10
30 minutes on machine A and 10 minutes on machine B
Answer:
Step-by-step explanation:
Presuming represents the length of the box (which you should have specified), your volume function:
is correct.
V(x)=-x^3+33x^2-90x=0
Obviously, in order to have a box, all three dimensions must be positive numbers.
Since the height is 3 less than the length, the length must be greater than 3 so that the height will be greater than zero. Since the sum of length and width is 30, the length must be less than 30. Hence, the possible range of values for is
If you know enough calculus to be able to take the derivative of this function, set the first derivative equal to zero and solve. You will obtain two possible extrema. Only one of these extrema will lie in the the acceptable range of values,
If you don't know the Calculus, then the best you can do is to graph the function and eyeball it.
C. Figure 3 because you can rotate it 180° and it will match up
The area of the rectangle is
3x4=13
The area of the triangle is 4
The total area will be 13+4=17