Question

The volume of a cube is 729cm^3. Find its surface area and the length of a diagonal.

Answer 1

Surface area=6l²
Cube 729=9cm
Surface area =6×81=486cm²

Diagonal =squareoot3×side
=1.732×9=15.58

Answer 2

volume of cube= a^3
729 =a^3
therefore,
a=√729
a=9 cm

now,surface area=6a^2
=6(9)^2
=6×81
=486 cm^2
now, length of diagonal
=√3 a
=√3×9
=√27
=5.196