Answer:
Step-by-step explanation:
Volume of the box = x³ +11x² + 20x – 32 I think the ' is a typo for ³
the width is x-1 and the height is x+8
Find an expression for the length
Vol = LWH solve L
Vol / (WH) = L so
L = (x³ +11x² + 20x – 32) / (x-1) (x+8)
so it would help to factor the numerator
(x³ +11x² + 20x – 32) I'm willing to bet (x-1) and (x+8) are factors
but I will plot the equation to find the three roots
(x³ +11x² + 20x – 32) = (x-1) (x+8) (x+4)
L = (x³ +11x² + 20x – 32) / (x-1) (x+8)
= (x-1) (x+8) (x+4) / (x-1) (x+8) the (x-1) and (x+8) cancel out leaving
L = (x + 4)
Replace n with 9 :
7 × 9 - 3 = 60
the answer is C.60
I assume there are some plus signs that aren't rendering for some reason, so that the plane should be

.
You're minimizing

subject to the constraint

. Note that

and

attain their extrema at the same values of

, so we'll be working with the squared distance to avoid working out some slightly more complicated partial derivatives later.
The Lagrangian is

Take your partial derivatives and set them equal to 0:

Adding the first three equations together yields

and plugging this into the first three equations, you find a critical point at

.
The squared distance is then

, which means the shortest distance must be

.
Answer:5 units!
Step-by-step explanation:
.