推 ckchi :(a+b)^2 = a^2 + b^2 + 2ab 03/14 14:28
→ ckchi :方便起見 兩股叫a b、斜邊叫c 03/14 14:29
→ ckchi :a+b+c = 40 => a+b = 40-c.....(1) 03/14 14:29
→ ckchi :a^2 + b^2 = c^2 .....(2) 03/14 14:29
→ ckchi :ab/2 = 30 => ab = 60 .....(3) 03/14 14:30
→ ckchi :把(1)~(3)帶入一開始的方程式可以求出c 03/14 14:30
→ mj813 :感恩! 03/14 14:55
推 XII :30=rs=(s-c)*20=>c=21.5=>h_c=60/21.5=120/43 03/14 15:19
→ binbinthink :c=21.5,a+b=18.5圍不成三角形,a+b應>c才對喔 03/14 15:39