Answer:
1020000is a hundredth tenths thousands
Answer:
150 feet by 300 feet.
Step-by-step explanation:
The fence is to enclose a rectangular area of 45,000 ft squared.
If the dimensions of the rectangle are x and y
Area of a rectangle = xy
- xy=45000

Perimeter of the Rectangle =2x+2y
Fencing material costs $ 3 per foot for the two sides facing north and south and $6 per foot for the other two sides.
- Cost of Fencing, C=$(6*2x+3*2y)=$(12x+6y)
Substitute
into the Cost to get C(y)
C=12x+6y

The value at which the cost is least expensive is at the minimum point of C(y), when the derivative is zero.


Recall,

Since x=150, y=300
The dimensions that will be least expensive to build is 150 feet by 300 feet.
If I’m using substitution the answer is A
Answer:
Not sure sorry
Step-by-step explanation:
New pump:
5 hours = 1 pool
1 hour = 1/5 pool
Old pump:
15h = 1 pool
1h = 1/15 pool
If both work together
1h = 1/5 + 1/15 = 4/15 pool
4/15 pool = 1 hour
1/15 pool = 1/4 hour
15/15 pool = 1/4 x 15
1 pool = 3.75 hours or 3 hours 45 mins