GRE考试

【单选题】In the figure below, vertex Q of square OPQR is on a circle with center O. If the area of the square is 8, what is the area of the circle



网考网参考答案：C
网考网解析：
Use TACTICS 2 and 4. On your scrap paper, extend line segments OP and OR. [*] Square OPQR, whose area is 8, takes up most of quarter-circle OXY. So the area of the quarter-circle is certainly between 11 and 13. The area of the whole circle is 4 times as great: between 44 and 52. Check the five choices: they are approximately 25, 36, 50, 100, 200. The answer is clearly C. **Another way to use TACTIC 4 is to draw in line segment OQ. [*] Since the area of the square is 8, each side is[*], and diagonal OQ is [*] But OQ is also a radius, so the area of the circle is π(4) 2 =16π. document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>