Page 36 - Engineering
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‫ﺍﳌﺴﺘﻘﻴﻤﺎﺕ ﻭﺍﻟﺰﻭﺍﻳﺎ ‪٢٣‬‬

                                     ‫ﻣﺴﺎﺋﻞ ﻣﺤﻠﻮﻟﺔ‬

‫)‪ [AJHSME 1989] (١‬إذا ﻛﺎﻧﺖ اﳌﺴﺎﻓﺔ ﺑﲔ اﻟﻨﻘﺎط ﻋﻠﻰ اﻟﻘﻄﻌﺔ اﳌﺴﺘﻘﻴﻤﺔ‬
                                    ‫‪ AB‬ﻣﺘﺴﺎوﻳﺔ ﻓﻤﺎ ﻗﻴﻤﺔ ‪ y‬؟‬

         ‫‪AB‬‬

‫)د( ‪16‬‬   ‫‪0‬‬          ‫‪y 20‬‬             ‫)أ( ‪8‬‬

            ‫)ج( ‪12‬‬       ‫)ب( ‪10‬‬

‫اﻟﺤﻞ‪ :‬اﻹﺟﺎﺑﺔ ﻫﻲ )ج(‪ :‬ﲟﺎ أن اﳌﺴﺎﻓﺔ ﺑﲔ ﲨﻴﻊ اﻟﻨﻘﺎط ﻣﺘﺴﺎوﻳﺔ ﻓﺈن اﳌﺴﺎﻓﺔ ﺑﲔ‬

         ‫أي ﻧﻘﻄﺘﲔ ﻣﺘﺘﺎﻟﻴﺘﲔ ﺗﺴﺎوي ‪ . 20 = 4‬إذن‪.y = 3 × 4 = 12 ،‬‬

                                       ‫‪5‬‬

‫)‪ (٢‬ﰲ اﻟﺸﻜﻞ اﳌﺮﻓﻖ ‪ .DAE = 19° ،BAC = 27° ،BAE = 73°‬ﻣﺎ‬
                                          ‫ﻗﻴﺎس اﻟﺰاوﻳﺔ ‪ CAD‬؟‬

                         ‫‪C‬‬     ‫‪B‬‬
                    ‫‪D‬‬

         ‫‪E‬‬

                            ‫‪A‬‬

‫)د( ‪32°‬‬  ‫)ج( ‪27°‬‬            ‫)ب( ‪23°‬‬  ‫)أ( ‪19°‬‬

         ‫اﻟﺤﻞ‪ :‬اﻹﺟﺎﺑﺔ ﻫﻲ )ج(‪ :‬ﻻﺣﻆ أن اﻟﺰواﻳﺎ ﻣﺘﺠﺎورة‪ ،‬وﻟﺬا ﻓﺈن‬

         ‫‪BAE = BAC + CAD + DAE‬‬
           ‫‪73° = 27° + CAD + 19°‬‬

         ‫‪CAD = 73° − 46° = 27°.‬‬
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