The area of a square is 49 sq mm. What is the length of each side of the square (in mm)?

Introduction / Context:
This question tests the inverse relationship between the area of a square and its side length. The area of a square is side^2. If the area is known, the side is found by taking the square root of the area. Since the area here is 49 sq mm, the side will be sqrt(49) mm. This is a simple recall and calculation question, but it is important to keep units straight: area is in square millimetres, so the side length will be in millimetres.

Given Data / Assumptions:

• Area of square = 49 sq mm
• Area formula: Area = side^2
• Side length = sqrt(Area)

Concept / Approach:
Compute side = sqrt(49). Since 49 is a perfect square (7*7), the answer is an integer in mm.

Step-by-Step Solution:
Area = side^2 49 = side^2 side = sqrt(49) = 7 So the side length is 7 mm

Verification / Alternative check:
Square the result to verify: 7^2 = 49. That matches the given area, confirming the computed side is correct.

Why Other Options Are Wrong:
5 mm gives area 25 sq mm, too small. 6 mm gives area 36 sq mm, still too small. 8 mm gives area 64 sq mm, too large. 9 mm gives area 81 sq mm, too large.

Common Pitfalls:
Forgetting to take square root, confusing area units with length units, or mistakenly dividing by 2 instead of applying sqrt.

Final Answer:
The side length of the square is 7 mm.