Answer:
x = 10 cm, y = 5 cm gives a minimum area of 300 cm^2.
Step-by-step explanation:
V= x^2y = 500
Surface area A = x^2 + 4xy.
From the first equation y = 500/x^2
So substituting for y in the equation for the surface area:
A = x^2 + 4x * 500/x^2
A = x^2 + 2000/x
Finding the derivative:
dA/dx = 2x - 2000x^-2
dA/dx = 2x - 2000/x^2
This = 0 for a minimum/maximum value of A, so
2x - 2000/x^2 = 0
2x^3 - 2000 = 0
x^3 = 2000/ 2 = 1000
x = 10
Second derivative is 2 + 4000/x^3
when x = 10 this is positive so x = 10 gives a minimum value of A.
So y = 500/x^2
= 500/100
= 5.
(9x^2-4)..........................
Answer:
the additional charge per minute because t represents the number of minutes
Step-by-step explanation:
Answer: Thus both of them got it correct
Step-by-step explanation:
Step 1
Andy finds the sale price of a baseball glove that normally costs $49 by evaluating the question 49 - 0.3(49).
the Price will be 49-14.7=34:3
Step 2
Juan finds the sale price by multiplying 0.7(49).
0.7x 49 =34.3
