Answer:
No. The only real solution is x = 4. It is not possible to cut squares of this size.
Step-by-step explanation:
Volume of the box is (6 - 2x)(3 - 2x)x = 40
2(3 - x)(3 - 2x)x = 40
Divide both sides by 2.
(3 - x)(3 - 2x)x = 20



On inspection, x = 4 is one of the solutions of the above cubic equation.
Now, divide the equation by x - 4, we get

The discriminant of this equation is:

= -39 < 0
Hence, x = 4 is the only real solution.
Since, 6 - 2x < 0, it is not possible to cur squares of side 4 in. at the corners.
Hence, the correct answer is:
No. The only real solution is x = 4. It is not possible to cut squares of this size.