推 Desperato : (AB/3)^2 + (2AC/3)^2 = 4^2 09/19 09:05
→ newperson : 讚哦 感謝 沒想到這方法 09/19 09:09
推 nobrother : 這方法好猛!! 09/19 09:14
推 wayne2011 : 既然是國競題~就代陳一理所編著"直方式"練習的"線段 09/19 10:06
→ wayne2011 : 平方和"等式,3[5^2+(a/3)^2]=2a^2,(5/3)a^2=75,a^2= 09/19 10:08
→ wayne2011 : 45,a=3sqrt(5),因而答案選(A),之前有跟D大講過那題. 09/19 10:10
推 rocketboy : 可否請D大開釋? 09/19 15:49
推 rocketboy : D大的方法,我懂了,感謝 09/19 15:59