Question

The total surface of a cube is 54 cm square. what is the length of its side​

Answer 1

Step-by-step explanation:

Since the surface area of a cube comprises six identical squares, the S.A. of a cube with edge length a is:

SA=6a2

We know the SA is 54 cm 2 and we want to find a, so we plug in what we know and solve for what we need:

54=6a2⟹546=a2⟹9=a2

⟹±3=a

However, the length of the edge of a cube can’t be negative, so a=3 cm.

Answer 2

Let length of each side of cube be 'a'

Total Surface area of cube = 6a²

→ 54 = 6a²

→ a² = 9

→ a = ± 3

Side of a cube cannot be negative

So, side of cube is 3 cm.

Additional information:

• TSA or Total Surface area of Cube is the sum of areas of all sides in cube including the top and bottom side. Since 6 sides are present in cube, TSA = 6a².
• CSA or Curved Surface Area is the sum of areas of all sides excluding top and bottom sides. So the CSA = 4s²