The solution to the system of linear equations is where the two lines intersect.
Look for the point where the two lines intersect. The x-value is 2 1/2, and the y-value is -4.
The answer is C.
if we name that part x, then we can say
1/x = 1/a + 1/b
Let width equal X and length equal X+2. Use algebra 72 = X times X+2
has critical points where the derivative is 0:
The second derivative is
and 
, which indicates a local minimum at 
with a value of 
.
At the endpoints of [-2, 2], we have 
and 
, so that has an absolute minimum of 
and an absolute maximum of 
on [-2, 2].
So we have
