Circle area formula is Area = ?

Circle area formula is Area = ?

• A. Area = π r²
• B. Area = 2π r
• C. Area = π r
• D. Area = π r³

Answer: (A)

The area of a circle grows with the square of the radius, with π as the constant that connects linear dimensions to area. This gives the formula A = π r². You can see why by thinking of a unit circle (radius 1): its area is π. If you scale all lengths by a factor r, areas scale by r², so the area becomes π r². Doubling the radius makes the area four times larger, not eight, which confirms the square relationship. The other expressions mix up different circle properties or dimensions: 2π r is the circumference, not area; π r lacks the necessary r² factor; π r³ doesn’t represent area at all (it resembles a volume term). Therefore, the correct area formula is π r².

The area of a circle grows with the square of the radius, with π as the constant that connects linear dimensions to area. This gives the formula A = π r². You can see why by thinking of a unit circle (radius 1): its area is π. If you scale all lengths by a factor r, areas scale by r², so the area becomes π r². Doubling the radius makes the area four times larger, not eight, which confirms the square relationship. The other expressions mix up different circle properties or dimensions: 2π r is the circumference, not area; π r lacks the necessary r² factor; π r³ doesn’t represent area at all (it resembles a volume term). Therefore, the correct area formula is π r².