Geometry and TrigonometryEasy–MediumArea of a square from its perimeter
Geometry and Trigonometry practice question
A square has a perimeter of 36. What is the area of the square?
- A. 81Correct
- B. 36
- C. 324
- D. 18
Answer: A. 81
A square's four sides are equal, so each side is 36 / 4 = 9. Area is side squared: 9² = 81.
Why the other answers are wrong
- B. 36
- 36 is the perimeter itself. Area is a different quantity — find the side length first (9), then square it.
- C. 324
- 324 is 36² / 4, squaring the perimeter before dividing. Divide the perimeter by 4 FIRST to get the side, then square: 9² = 81.
- D. 18
- 18 is 36 / 2. A square has four sides, not two, so each side is 36 / 4 = 9.
More Geometry and Trigonometry questions
- Easy–Medium
A circle has a radius of 6. What is its area? (Use A = πr².) - Easy–Medium
A right triangle has legs of length 6 and 8. What is the length of the hypotenuse? - Easy–Medium
A circle has a radius of 5. What is its circumference? (Use C = 2πr.) - Easy–Medium
What is the midpoint of the segment joining the points (2, 3) and (8, 11)? - Easy–Medium
What is the measure, in degrees, of angle B? - Easy–Medium
What is the area, in square centimeters, of the trapezoid?
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