GRE考试

【单选题】
If the lengths of two of the sides of a triangle are 9 and 10, which of the following could be the length of the third side
Ⅰ. 1
Ⅱ. 11
Ⅲ. 21A．None
B．Ⅰ only
C．Ⅱ only
D．Ⅰ and Ⅱ only
E、Ⅰ, Ⅱ, and Ⅲ

网考网参考答案：C
网考网解析：
By the triangle inequality (KEY FACTS J12 and J13), · The third side must be less than 9 + 10 = 19. (Ⅲ is false.) · The third side must be greater than 10 -9 = 1. (Ⅰ is false.) · Any number between 1 and 19 could be the length of the third side. (Ⅱ is true.) The answer is C. document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>