Final answer:
The inequality formed from the condition that the length (3x cm) of a rectangle is greater than its width (x + 5 cm) is 3x > x + 5. Upon simplifying, we find that x must be greater than 2.5.
Step-by-step explanation:
The question asks to form and solve an inequality where the length of a rectangle, given as 3x cm, is greater than its width, given as (x + 5) cm. To represent this inequality, we would write: 3x > x + 5
To solve for x, we subtract x from both sides: 2x > 5
Now, divide both sides by 2 to isolate x: x > 2.5
Therefore, x must be greater than 2.5 for the length to be greater than the width.