I'd say its D but im not quite sure, its what makes most sense to me.
Answer:
a = c + 16
Step-by-step explanation:
a = b + 12
b = c + 4
Solve for b in the first equation.
a = b + 12
a - 12 = b
Put b as a - 12 in the second equation and solve for a.
a - 12 = c + 4
a = c + 4 + 12
a = c + 16
Slope Formula:
m= Y2-Y1/X2-X1
m= 8-12 / 3-2
m= -4/ 1
m= -4
Therefore, the equation of the line is y=-4x+20
Check the picture below.
as you can see, the graph of the volume function comes from below goes up up up, reaches a U-turn then goes down down, U-turns again then back up to infinity.
the maximum is reached at the close up you see in the picture on the right-side.
Why we don't use a higher value from the graph since it's going to infinity?
well, "x" is constrained by the lengths of the box, specifically by the length of the smaller side, namely 5 - 2x, so whatever "x" is, it can't never zero out the smaller side, and that'd happen when x = 2.5, how so? well 5 - 2(2.5) = 0, so "x" whatever value is may be, must be less than 2.5, but more than 0, and within those constraints the maximum you see in the picture is obtained.