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<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">解：如图，过点<i>C</i>作<i>CF</i>⊥<i>AB</i>于点<i>F</i>．</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">设塔高<i>AE</i>＝<i>x</i>，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">由题意得，<i>EF</i>＝<i>BE</i>﹣<i>CD</i>＝56﹣27＝29<i>m</i>，<i>AF</i>＝<i>AE</i>+<i>EF</i>＝（<i>x</i>+29）<i>m</i>，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">在Rt△<i>AFC</i>中，∠<i>ACF</i>＝36°52′，<i>AF</i>＝（<i>x</i>+29）<i>m</i>，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">则<i>CF</i>＝</span></span></span></span></span><img height="35" src="/uploads/meth/20210403/734d6353b07a34f22cc74d3b04bcfcca.png" width="93" /><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">≈</span></span></span></span></span><img height="35" src="/uploads/meth/20210403/0c47c11bae57bd0b0d9cdc98d359a27f.png" width="37" /><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">＝</span></span></span></span></span><img height="35" src="/uploads/meth/20210403/20bd4893ce11f5140413853145039f40.png" width="13" /><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><i><span style="line-height:150%"><span style="font-family:宋体">x</span></span></i><span style="line-height:150%"><span style="font-family:宋体">+</span></span></span></span></span><img height="35" src="/uploads/meth/20210403/488007d1012dabbc02e6d0384ec595da.png" width="29" /><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">在Rt△<i>ABD</i>中，∠<i>ADB</i>＝45°，<i>AB</i>＝<i>x</i>+56，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">则<i>BD</i>＝<i>AB</i>＝<i>x</i>+56，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">∵<i>CF</i>＝<i>BD</i>，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">∴<i>x</i>+56＝</span></span></span></span></span><img height="35" src="/uploads/meth/20210403/a0b0d1353c8ebc7b14d974666cfc0421.png" width="13" /><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><i><span style="line-height:150%"><span style="font-family:宋体">x</span></span></i><span style="line-height:150%"><span style="font-family:宋体">+</span></span></span></span></span><img height="35" src="/uploads/meth/20210403/4e253e2b7fcc9697c039fbeca193e36e.png" width="29" /><span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">解得：<i>x</i>＝52，</span></span></span></span></span><br />
<span style="font-size:10.5pt"><span style="line-height:150%"><span style="font-family:Calibri"><span style="line-height:150%"><span style="font-family:宋体">答：该铁塔的高<i>AE</i>为52米．</span></span></span></span></span><br />
<img height="167" src="/uploads/meth/20210403/a6ae78183b9943fff245fbb2e68ab164.png" width="253" />

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