Answer:
5 years=$10
Step-by-step explanation:
count by 5's
There are going to be two solutions because the "biggest" x is x^2 but you can factor to find what they actually are.
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.
Both variables (x) are 3.
4×3=12
12-2=10
16×3=48
48-8=40
3 fits the variable of the missing number.
3 x 2.7 is the same as 3 x 3 x 0.9 = 9 x 0.9 = 8.1
