Question

One side of a cube has an area of 25 centimeters squared. What is the surface area of the cube?

Answer 1

a cube has all equal sides, so every face in the cube is just a square, if the area of one of those square is 25 cm², that simple means,


`\bf \textit{area of a square}\\\\ A=s^2~~ \begin{cases} s=length~of\\ \qquad a~side\\ ------\\ A=25 \end{cases}\implies 25=s^2\implies √(25)=s\implies 5=s`

now, look at the picture below, a cube is really just 6 squares stacked up to each other at the edges, in this case, all 6 squares are 5x5.

so, simply get the area of all of them, and sum them up, and that's the surface area of the cube.

(5*5)+(5*5)+(5*5)+(5*5)+(5*5)+(5*5).