Page 119 - Engineering
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‫ﺍﳍﻨﺪﺳﺔ )ﺍﳉﺰء ﺍﻷﻭﻝ(‬                        ‫‪١٠٦‬‬

       ‫‪XY = 4x 2 + 4y2 = 2 x 2 + y2 = 2 169 = 26 .‬‬

‫)‪ [AMC10B 2004] (٤٠‬اﳌﺜﻠﺚ ‪ △ACE‬ﻗﺎﺋﻢ اﻟﺰاوﻳﺔ ﻓﻴﻪ ‪،AC = 12‬‬
‫‪ .EA = 20 ،CE = 16‬رﲰﻨﺎ اﻟﻨﻘﺎط ‪ F ،D ،B‬ﻋﻠﻰ ‪،CE ،AC‬‬
‫‪ EA‬ﻋﻠﻰ اﻟﺘﻮاﱄ ﲝﻴﺚ ﻳﻜﻮن ‪ .EF = 5 ،CD = 4 ،AB = 3‬ﻣﺎ ﻧﺴﺒﺔ‬

                ‫ﻣﺴﺎﺣﺔ اﳌﺜﻠﺚ ‪ △DBF‬إﱃ ﻣﺴﺎﺣﺔ اﳌﺜﻠﺚ ‪ △ACE‬؟‬

‫)د( ‪7‬‬       ‫)ج( ‪11‬‬  ‫)ب( ‪3‬‬            ‫)أ( ‪1‬‬

‫‪16‬‬           ‫‪25‬‬     ‫‪8‬‬                ‫‪4‬‬
       ‫‪A‬‬
                              ‫اﻟﺤﻞ‪ :‬اﻹﺟﺎﺑﺔ ﻫﻲ )د(‪:‬‬

       ‫‪3‬‬

       ‫‪B 15‬‬

        ‫‪9‬‬                     ‫‪F‬‬
       ‫‪Gh‬‬                         ‫‪5‬‬

       ‫‪C 4D‬‬         ‫‪12‬‬               ‫‪E‬‬

                                         ‫ﻻﺣﻆ أوﻻً أن‬

          ‫‪AB = CD = EF = 1‬‬
          ‫‪AC CE EA 4‬‬

                     ‫‪BC = DE = FA = 3‬‬
                     ‫‪AC CE EA 4‬‬

‫ارﺳﻢ اﻵن اﻻرﺗﻔﺎع ‪ h‬ﻣﻦ ‪ F‬إﱃ ‪ AC‬ﻟﻴﻼﻗﻲ ‪ AC‬ﰲ اﻟﻨﻘﻄﺔ ‪ .G‬ﻋﻨﺪﺋﺬ‪،‬‬

              ‫‪.(AA) △AFG ∼ △AEC‬‬
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