直角梯形知道上底高度坡比怎么算下底
\u77e5\u9053\u68af\u5f62\u7684\u4e0a\u5e95\u548c\u9ad8\u4ee5\u53ca\u68af\u5f62\u7684\u5761\u6bd4\u600e\u4e48\u6c42\u77e5\u4e0b\u5e95\u5982\u56fe\uff0c\u4e3a\u68af\u5f62\u7684\u53f3\u534a\u90e8\u5206\u3002
\u5761\u6bd4=h/l
l=h/\u5761\u6bd4
\u7528\u540c\u6837\u65b9\u6cd5\u8ba1\u7b97\uff0c\u5de6\u534a\u90e8\u5206\u7684l\uff0c\u8bb0\u4e3al\u2032
\u68af\u5f62\u7684\u4e0b\u5e95=\u4e0a\u5e95+l+l\u2032
\u8fc7C\u70b9\u4f5cDB\u7684\u5e73\u884c\u7ebf\u4ea4AB\u5ef6\u957f\u7ebf\u4e8eE\uff0c\u4e09\u89d2\u5f62ACE\u662f\u76f4\u89d2\u8fb9\u76f8\u7b49\u7684\u7b49\u8170\u76f4\u89d2\u4e09\u89d2\u5f62\uff0c\u5176\u9762\u79ef\u4e0e\u68af\u5f62\u9762\u79ef\u76f8\u7b49\u4e3a00\uff0c\u6240\u4ee5\uff0cACXCE=AEXCF=200\uff0c\uff08CF\u662f\u9ad8\uff09\uff0c\u8fd9\u6837\u4f60\u5c31\u884c\u4e86
依题意，求b，已知h=2.5 a=0.2 坡比=h/L=1/0.3，带入h=2.5,可以得L=2.5*0.3/1=0.75,而b=a+L,带入a和L的值得到b=0.75+0.2=0.95
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绛旓細灏忛1: 灏忛2: 锛1锛変綔鍑轰袱鏉楂锛屽緱鍒颁袱涓鐩磋涓夎褰㈠強涓涓煩褰紟鍒╃敤鍕捐偂瀹氱悊鍙鍧℃瘮寰楀埌BF锛孉E闀裤傦紙2锛夊埄鐢ㄥ潯姣旂殑瀹氫箟锛屽嵆鍙緱鍑鸿繋姘村潯BC鐨勫潯姣旂殑鍊笺傦紙1锛夊鍥撅紝浣淐F鈯B锛孌E鈯D锛屽瀭瓒冲垎鍒负鐐笷锛孍銆傗埓鍥涜竟褰DEF鏄煩褰紟鈭碈F=DE=4锛孍F=CD=2銆傗埓BF=CFcot30掳=4 锛孉E=1.5...
绛旓細1銆100*2^0.5/(16-8)=25/2*2^0.5 娴烽噷/鏃 2銆丄B=2+1+2/tan30=3+2*3^0.5 S=(AB+CD)*h/2 =4+2*3^0.5骞虫柟绫
绛旓細锛1锛変綔楂AE銆丏F锛屽彲寰楀埌鐭╁舰AEFD鍜鐩磋涓夎褰ED鍜孌FC鈭碅E=DF=2鈭碋F=AD=3鈭礎B鐨鍧℃瘮鏄1锛0.5鈭碆E=1鈭碘垹C=30掳鈭碈F=2 3 鍒欙細涓嬪簳瀹紹C=4+2 3 锛坢锛夛紙2锛夆埖S 姊舰ABCD =7+2 3 锛坢 2 锛夆埓淇繖鏉￠槻娲牑闇瑕侊紙7+2 3 锛壝1000=7000+2000 3 锛...
