ce 99 mc X2
2012-04-07 9:58 pm
圖片參考：http://imgcld.yimg.com/8/n/HA07941386/o/701204070033513873390300.jpg
thanks a lots 20 POINTS!!!
回答 (1)
2012-04-07 10:46 pm
✔ 最佳答案
50)∠ACT = ∠BTA (∠in alt. segment)∠CAT = ∠CAT (common)△ATB ~ △ACT (A.A.)AT/9 = (16 + 9)/ATAT² = 9 * 25AT = 15(C)44)△NAD ~ △NCM
So
MN : ND = MC : AD = 1 : 2
So
△NCD = (2/3) △DMC = (2/3) (1/4)ABCD = (1/6)ABCDABMN
= △ABC - △NCM
= (1/2)ABCD - (1/3) △DMC
= (1/2)ABCD - (1/3) (1/4)ABCD
= (5/12) ABCD△NCD : ABMN
= (1/6)ABCD : (5/12) ABCD
= 1/6 : 5/12
= 2 : 5(D)
收錄日期: 2021-04-21 22:24:22
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20120407000051KK00335