Answer:

Step-by-step explanation:



The answer is 78. This is because you change 8 2/3 into a improper fraction which is 26/3. Then do 26/3×9/1. You should cross cancel so cancel out 3 and change it into 1 and change 9 into 3. So now your problem is 26×3=78.
~JZ
Hope it helps.
Answer:
umm i'm not rly sure what's going on here...but here's how i'd do it
Step-by-step explanation:
3280.84x12=39370.08 which is about 3,9370 feet.
to double check let's do an algebraic expression
1/3280.84=x/12 cross multiply
x(1)=3280.84(12) simplify
x=39370.08
hope that helped.
Given Information:
Area of rectangle = 16 square feet
Required Information:
Least amount of material = ?
Answer:
x = 4 ft and y = 4 ft
Step-by-step explanation:
We know that a rectangle has area = xy and perimeter = 2x + 2y
We want to use least amount of material to design the sandbox which means we want to minimize the perimeter which can be done by taking the derivative of perimeter and then setting it equal to 0.
So we have
xy = 16
y = 16/x
p = 2x + 2y
put the value of y into the equation of perimeter
p = 2x + 2(16/x)
p = 2x + 32/x
Take derivative with respect to x
d/dt (2x + 32/x)
2 - 32/x²
set the derivative equal to zero to minimize the perimeter
2 - 32/x² = 0
32/x² = 2
x² = 32/2
x² = 16
x =
ft
put the value of x into equation xy = 16
(4)y = 16
y = 16/4
y = 4 ft
So the dimensions are x = 4 ft and y = 4 ft in order to use least amount of material.
Verification:
xy = 16
4*4 = 16
16 = 16 (satisfied)
X and y vary directily means
y=kx
72=3k
divide both sides by 3
24=k
k=24
y=72