One system of equations would be
L = w+4
H = w-10
4H + 8(wL) = 1544
There is one viable solution; the width is 12, the length is 16, and the height is 2.
Using substitution with the system of equations, we have
4(w-10)+8(w(w+4))=1544
4w-40+8(w²+4w)=1544
4w-40+8w²+32w=1544
Combining like terms, we have
8w²+36w-40=1544
Factoring out a 4, we have
4(2w²+9w-10)=1544
Dividing both sides by 4 gives us
2w²+9w-10=386
Subtract 386 from both sides to get
2w²+9w-396=0
Using the quadratic formula, we have

Since a negative width makes no sense, we know that w=12.
This means L=w+4=12+4=16 and H=w-10=12-10=2
D(1/x)/dx= d(x^-1)/dx
= -x^-2
the derivatives of the two cases you mentioned is as follows:
(I) f(x)=k/x
d{f(x)}/dx= k×(-x^-2)
= -kx^-2
(ll) f(x)=x/k
d{f(x)}= d(x/k)/dx
= 1/k
you can just simply take out the constant from the derivative and multiply it to the final answer of the derivative of the given function.
136.75 is the answer to this equation
B is the correct answer im pretty sure