Answer:
8
Step-by-step explanation:
I thought I knew it but I don’t sorry.
5x + y = 3
y = 3 - 5x
Substitute this value into second equation,
8x + 5y = 7
8x +5(3 - 5x) = 7
8x + 15 - 25x = 7
-17x = 7 - 15
x = 8/17
Now, substitute it into first equation,
y = 3 - 5x
y = 3 - 5*8 / 17
y = 3 - 40/17
y = 11/17
In short, Your Answers would be: x = 8/17 & y = 11/17
Hope this helps!
Answer:
2
Step-by-step explanation:
produces a straight line
Answer:
the optimal dimensions of the rectangle in order to minimize cost are
19.1 ft x 47.74 ft
Step-by-step explanation:
Assuming that the area is rectangular shaped, then
Cost = cost of the pine board fencing * length of pine board fencing + cost of galvanized steel fencing * length of galvanized steel fencing
C = a*x + b*y
that is constrained by the area
Area= A= x*y → y= A/x
replacing in C
C = a*x + b* A/x
the minimum cost is found when the derivative of the cost with respect to the length is 0 , then
dC/dx = a - b*A/x² = 0 → x = √[b/a*A]
replacing values
x = √[b/a*A] = √[($2/ft/$5/ft)*912 ft²] = 19.1 ft
then for y
y= A/x = 912 ft²/19.1 ft = 47.74 ft
then the optimal dimensions of the rectangle in order to minimize cost are
19.1 ft x 47.74 ft