Geometry: The area of a circle can be determined by which of the following formulas?
-
½ base x height
-
2?r (2 pie r)
-
x+y
-
?r2 (pie r square)
D
Correct answer
Explanation
The area of a circle is calculated using the formula A = πr², where π (pi) is approximately 3.14159 and r is the radius of the circle. Option B '2πr' gives the circumference, not area. Option A '½ base × height' is for triangles. Option C 'x + y' is a simple algebraic expression with no geometric meaning. The area formula πr² is fundamental to geometry.