Jawapan

2016-02-08T17:29:32+08:00
AO²=OB²+BA²                     DO²=DE²+EO²                BE=BO+OE

25²=OB²+15²                         25²=12²+EO²                 BE=20+21.93

625=OB²+225                        625=144+EO²                BE=41.93 cm 
OB²=625-225                            EO²=625-144
OB=√400                                    EO=√481
OB=20                                         EO =21.93
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