求教：Prep-PS2 第111和158题解题思路

Kathy919

111. In the figures above, if the area of the triangle on the right is twice the area of the triangle on the left, then in terms of s, S =

(A)  s乘2分子根号2
(B)  s乘2分子根号3
(C)  s乘根号2
(D)  s乘根号3
(E) 2s

答案是C

158. If x and y are positive, which of the following must be greater than   [?]

[?]

(A)    
(B) None
(C) I only
(D) II only
(E) I and III

evek

晕。。。没图

ywsunny

111. 这2个三角形是相似△。所以边的比的平方等于面积比。也就是（S/s)²=大△面积/小△面积