Answer:
400 m^2.
Step-by-step explanation:
The largest area is obtained where the enclosure is a square.
I think that's the right answer because a square is a special form of a rectangle.
So the square would be 20 * 20 = 400 m^2.
Proof:
Let the sides of the rectangle be x and y m long
The area A = xy.
Also the perimeter 2x + 2y = 80
x + y = 40
y = 40 - x.
So substituting for y in A = xy:-
A = x(40 - x)
A = 40x - x^2
For maximum value of A we find the derivative and equate it to 0:
derivative A' = 40 - 2x = 0
2x = 40
x = 20.
So y = 40 - x
= 40 - 20
=20
x and y are the same value so x = y.
Therefore for maximum area the rectangle is a square.
The answer
the question is not clear
if it is to determine how to write this phrase as a mathematics equation, it is as follow:
let be x the unknown number
so <span>ighty-seven decreased by three times a number is greater than one hundred sixty-five means 87 - 3x>165,
so we can solve it easily as 87 - 165> 3x, and then 3 x > 32, and finally the value of x is x > 32/3=10.66</span>
Answer:
C: 2
Step-by-step explanation:
I looked it up on google it is 1252
He mails
(1000) x (the number of weeks he keeps it up)
of them.
