Answer:
In the equation, it divides 21 by x before knowing what x is, and gets it incorrect. Instead, you need to divide 21 by -4.2.
Step-by-step explanation:
-4.2x = 21
-------------
-4.2
x = -5
Area of circle= 3.14r^2
r= 4
A= 50.27
287.496 in^3 since you take 6.6 * 6.6 *6.6 that should give you your answer
Answer:
V(max) = 8712.07 in³
Dimensions:
x (side of the square base) = 16.33 in
girth = 65.32 in
height = 32.67 in
Step-by-step explanation:
Let
x = side of the square base
h = the height of the postal
Then according to problem statement we have:
girth = 4*x (perimeter of the base)
and
4* x + h = 98 (at the most) so h = 98 - 4x (1)
Then
V = x²*h
V = x²* ( 98 - 4x)
V(x) = 98*x² - 4x³
Taking dervatives (both menbers of the equation we have:
V´(x) = 196 x - 12 x² ⇒ V´(x) = 0
196x - 12x² = 0 first root of the equation x = 0
Then 196 -12x = 0 12x = 196 x = 196/12
x = 16,33 in ⇒ girth = 4 * (16.33) ⇒ girth = 65.32 in
and from equation (1)
y = 98 - 4x ⇒ y = 98 -4 (16,33)
y = 32.67 in
and maximun volume of a carton V is
V(max) = (16,33)²* 32,67
V(max) = 8712.07 in³