You need to divide the miles by the hours to et the Average speed.
M divided by h = s
Because to get the mph (miles per hour) you multiply the average speed to the hours.
S•h=mph
Answer:
It equals 10.5
Step-by-step explanation:
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.
When you have
you can solve the equation by multiplying both sides by 1/4. Then simplify.
