Ob has 50 feet of fencing to enclose a rectangular garden. if one side of the garden is x feet long, he wants the other side to be (25 – x) feet wide. what value of x will give the largest area, in square feet, for the garden?

a. 5

b. 10

c. 15

d. 12.5

Respuesta :

A = x(25-x)

we want the value of x which gives maximum A.

we can use calculus to do this

dA/dx = 25 - 2x = 0    for maximum area

2x = 25

x = 12.5