From the title, we can know that cutting two knives into three squares is the two knives shown in the red line in the picture.
So the bottom of a cuboid is square, and its height is three times the length of the bottom.
S length = 2xl 2+lx3lx4 = 126? Get L=3? So s is positive = l 2x6 = 54 (s = rectangular surface area, L= base length of cuboid).
S table =54x3= 162
2. The perimeter from the bottom is18cm, the bottom area is 20cm, c =18cm, and the bottom of s =20?
That is 2x(a+b)= 18 and ab=20, then the two lengths of the bottom are 4 and 5 respectively.
S total = 184=2ab+2h? x9
So h=8
So the volume V=20x8= 160.