一个圆,面积为314平方厘米,求它的半径，直径和周长。
\u4e00\u4e2a\u5706\u7684\u76f4\u5f84\u662f14\u5398\u7c73\uff0c\u5b83\u7684\u5468\u957f\u662f______\u5398\u7c73\uff0c\u9762\u79ef\u662f______\u5e73\u65b9\u5398\u7c733.14\u00d714=43.96\uff08\u5398\u7c73\uff093.14\u00d7\uff0814\u00f72\uff09 2 =153.86\uff08\u5e73\u65b9\u5398\u7c73\uff09\u7b54\uff1a\u5b83\u7684\u5468\u957f\u662f43.96\u5398\u7c73\uff0c\u9762\u79ef\u662f153.86\u5e73\u65b9\u5398\u7c73\uff0e\u6545\u7b54\u6848\u4e3a\uff1a43.96\uff0c153.86\uff0e
\u5706\u7684\u5468\u957f\uff1d2\u00d7\u534a\u5f84\u00d7\u5706\u5468\u7387\uff1d\u76f4\u5f84\u00d7\u5706\u5468\u7387
\u5706\u7684\u9762\u79ef=\u534a\u5f84\u7684\u5e73\u65b9\u00d7\u5706\u5468\u7387
\u5706\u5468\u7387 \u03c0 \u22483.14
\u5468\u957f\uff1aC=2\u00d73\u00d7\u03c0 =6\u03c0\uff08cm²\uff09 6\u03c0=18.84 \uff08cm²\uff09
\u9762\u79ef\uff1aS=3² \u00d7\u03c0 =9\u03c0\uff08cm²\uff09 9\u03c0=28.26 \uff08cm²\uff09
πr²=314，所以，r=10，直径d=2r=20，周长L=2πr=31.4
绛旓細314/3.14锛100 r锛10cm
绛旓細314梅3.14=100锛骞虫柟鍘樼背锛夛紝鍥犱负10脳10=100锛屾墍浠ヨ繖涓渾鐨勫崐寰勬槸10鍘樼背锛庣瓟锛氳繖涓渾鐨勫崐寰勬槸10鍘樼背锛
绛旓細100鍘樼背
绛旓細鍦嗙殑鐩村緞鍗虫鏂瑰舰瀵硅绾胯繎浼间负20鍘樼背锛姝ｆ柟褰㈣竟闀*姝ｆ柟褰㈣竟闀+姝ｆ柟褰㈣竟闀*姝ｆ柟褰㈣竟闀=20*20锛屾晠姝ｆ柟褰闈㈢Н涓200
绛旓細鍦嗙殑闈㈢Н涓314骞虫柟鍘樼背,鍒欏崐寰勭殑骞虫柟鏄314/3.14=100 鎵浠,鍗婂緞鏄10鍘樼背,鐩村緞鏄20鍘樼背,鍛ㄩ暱鏄3.14*20=62.8鍘樼背
绛旓細璁惧崐寰勪负x閲岀背 3.14脳x²=314 x²=314梅3.14 x²=100 x=卤10 鍥犱负鏄崐寰勬墍浠=10鍘樼背
绛旓細鍗婂緞=鈭氾紙314梅3.14锛=10鍘樼背 鏈嬪弸锛岃閲囩撼姝ｇ‘绛旀锛屼綘浠彧鎻愰棶锛屼笉閲囩撼姝ｇ‘绛旀锛屽洖绛旈兘娌℃湁鍔诧紒锛侊紒鏈嬪弸锛岃銆愰噰绾崇瓟妗堛戯紝鎮ㄧ殑閲囩撼鏄垜绛旈鐨勫姩鍔涳紝濡傛灉娌℃湁鏄庣櫧锛岃杩介棶銆傝阿璋
绛旓細鍦嗛潰绉=3.14涔樺崐寰勪箻鍗婂緞 3.14涔樺崐寰勪箻鍗婂緞=314 鎵浠ュ崐寰勪箻鍗婂緞=100,鍥犱负10涔10=100,鎵浠ュ崐寰勬槸10,鐩村緞鏄20
绛旓細鍏堟眰鍘熷崐寰剅²=S/蟺=314/3.14=100 鍒檙=10锛cm锛夊崐寰勫鍔2cm鍚庡彉鎴愪负R=12cm锛屽垯澧炲姞2鍘樼背鍚庣殑鍛ㄩ暱C2=2蟺R=2脳3.14脳12=75.36锛坈m锛夊師鏉ョ殑鍛ㄩ暱C1=2蟺r=2脳3.14脳10=62.8锛坈m锛夊鍔犵殑鍛ㄩ暱涓:澧炲姞涓緞鍚庣殑鍛ㄩ暱-鍘熸潵鐨勫懆闀 =75.36-62.8=12.56锛坈m锛...
绛旓細浣犲ソ锛佽В锛氬渾鐨勫崐寰勬槸姝ｆ柟褰㈢殑瀵硅绾裤傚凡鐭ワ紝鍦嗙殑闈㈢Н=蟺r^2=3.14*r^2=314, r^2=100,r=10鍘樼背 鐩村緞=2r=20鍘樼背 鍦ㄦ鏂瑰舰涓紝鐢卞嬀鑲″畾鐞嗗緱锛氳竟闀縙2+杈归暱^2=20^2=400锛2杈归暱^2=400,杈归暱^2=200=姝ｆ柟褰㈢殑闈㈢Н 鎵浠ワ細闃村奖闈㈢Н=314-200=114骞虫柟鍘樼背 濡傛灉鏈鏈変粈涔堜笉鏄庣櫧鍙互杩介棶锛...
