Question

a cube has a surface area of 216 cm². what is the length of one side? 6 cm 18 cm 9 cm 12 cm

Explanation:

Step1: Recall cube surface area formula

A cube has 6 identical square faces. Let side length be $s$. Surface area $SA = 6s^2$.

Step2: Set up equation with given SA

$$216 = 6s^2$$

Step3: Solve for $s^2$

Divide both sides by 6: $\frac{216}{6} = s^2$ → $s^2 = 36$

Step4: Calculate side length $s$

Take square root: $s = \sqrt{36} = 6$

Answer:

A. 6 cm