求解初三数学题，谢谢，可悬赏 初三数学题，急求，悬赏50分！！！
\u521d\u4e09\u6570\u5b66\u9898\uff0c\u6c42\u89e3\uff01\uff01\uff01\u9ad8\u60ac\u8d4f\uff01(1)
\u4e00\u671f\u5de5\u7a0b\u5e74\u4ea7\u503c\uff1a(3.5\u4e07\u5428/7\u5428)*4\u4e07=2\u4ebf
(2)
\u8bbe\u4e00\u671f\u5de5\u7a0b\u65f6\u4eba\u6570\u4e3aX\u4eba\uff0c\u4e8c\u671f\u4eba\u6570\u589e\u957f\u767e\u5206\u6bd4\u4e3aP
\u7531\u4e8e\u4eba\u6570\u589e\u957f\u7684\u767e\u5206\u6570\u662f\u5e74\u4ea7\u503c\u589e\u957f\u767e\u5206\u6570\u76842.5\u500d
\u90a3\u4e48\uff0c\u9879\u76ee\u5efa\u6210\u540e\uff0c\u4e0e\u4e00\u671f\u5de5\u7a0b\u76f8\u6bd4\uff0c\u589e\u957f\u7387\u4e3ap/2.5\uff0c\u5e74\u4ea7\u503c\u4e3a2*\uff08p/2.5\uff09\u4ebf
\u5c31\u4e1a\u4eba\u5458\u589e\u52a02500\u4eba\uff0c\u6709\uff1aX*P=2500\u2026\u2026(1)
\u4eba\u6570\u589e\u957f\u7684\u767e\u5206\u6570\u662f\u5e74\u4ea7\u503c\u589e\u957f\u767e\u5206\u6570\u76842.5\u500d\uff0c\u5e76\u4e14\u9879\u76ee\u5efa\u6210\u540e\u6240\u6709\u5c31\u4e1a\u4eba\u5458\u7684\u4eba\u5747\u5e74\u4ea7\u503c\u662f\u4e00\u671f\u5de5\u7a0b\u65f6\u4eba\u5747\u5e74\u4ea7\u503c\u7684\u4e00\u534a
\u90a3\u4e48\u6709\uff1a2*(P/2.5)/(X+2500)=(2/X)/2 (\u7b49\u5f0f\u5de6\u8fb9\u662f\u6574\u4e2a\u9879\u76ee\u5efa\u6210\u540e\u4eba\u5747\uff0c\u53f3\u8fb9\u662f\u4e00\u671f\u4eba\u5747\u9664\u4ee52)
\u5373\uff0c5px=x+2500\u2026\u2026(2)
\u6839\u636e(1)(2)\u89e3\u5f97\uff1a X=10000 ,P=4%
\u90a3\u4e48\uff0c\u5de5\u7a0b\u5efa\u6210\u540e\u7684\u4eba\u6570\u662f 10000+2500=12500\u4eba
\u6240\u4ee5\u53ef\u4ee5\u89e3\u51b312500\u4eba\u5c31\u4e1a
1.
\u8bbe2010\u5e74\u63d0\u4f9b\u7684\u5c97\u4f4d\u4e3ay\u4e07\u4e2a
3+y+y(1+20%)=11.8
3+2.2y=11.8
2.2y=8.8
y=4
\u7b54\uff1a2010\u5e74\u7ecf\u6d4e\u589e\u957f\u4e3a\u5f53\u5730\u63d0\u4f9b\u7684\u5c31\u4e1a\u5c97\u4f4d\u67094\u4e07\u4e2a
2.
2009\u5e74\u9500\u552e\u989d\u4e3a\uff1a3\u00f775\u00d78=8/25\u4ebf
8/25+8/25\u00d7(1+x)+8/25\u00d7\uff081+x)^2=26.48
1+\uff081+x)+(1+x)^2=82.75
2+x+1+2x+x^2=82.75
x^2+3x-79.75=0
x\u2248755.54%\u6216x\u2248-1055.54%\uff08\u820d\u53bb\uff09
2011\u5e74\u9500\u552e\u989d\uff1a
8/25\u00d7(1+755.54%)^2=23.4223581312
2011\u5e74\u9500\u552e\u989d\u6240\u5360\u7684\u767e\u5206\u6bd4\uff1a
23.4223581312\u00f726.48\u224888.45%
\u9898\u76ee\u6709\u4e9b\u770b\u4e0d\u61c2\u3002\u3002\u5927\u6982\u5982\u6b64\u5427\u3002\u3002
解答过程图
此题第二问中要求直接写出BH长度很有误导性。
简要过程见附图。
绛旓細1 璁捐矾绋嬩负S,鑸归熶负x姘存祦閫熷害涓簓 S/(x+y)=6 S/(x-y)=8 瑙ｅ緱 x=7S/48 y=S/48 鏃堕棿t=璺▼/閫熷害 =S/锛圫/48)=48灏忔椂 闇瑕48灏忔椂 2 1. 1800:2000=9:10 2. 9*[1+0.2]=10.8 绾,缁夸袱闃熷墿浣欒矾绋嬫瘮: 1200/1000=1.2 绾,缁夸袱闃熼熷害姣: 10.8/10=1.08 1.2>1.08,缁...
绛旓細鍒濅笁鏁板棰橈紝姹傚闇歌В 24 锛岋紙1锛夎В锛氱敱棰樻剰寰 y=(8-3)*x+(12-5)*(500-x) y=-2x+3500 (2)瑙ｏ細鐢遍鎰忓緱 -2x+3500>=3200 x<=150 鎵浠ユ渶澶氳喘杩涚敳鐜╁叿150涓 25 锛1锛夎瘉鏄庯細鍥犱负鍥涜竟褰BCD鏄鏂瑰舰 鎵浠D=AB=BC 瑙扐BD=瑙扖BD=45搴 瑙扐BC=瑙払CD=90搴 鍥犱负BE...
绛旓細1銆佲埖ABCD鏄鏂瑰舰 鈭粹垹B=鈭燙=90掳 鈭礎M鈯N锛岄偅涔堚垹AMB+鈭燙MN=180掳-鈭燗MN=90掳 鈭燘AM+鈭燗MB=90掳 鈭粹垹BAM=鈭燙MN 鈭碘垹B=鈭燙 鈭燘AM=鈭燙MN 鈭碦T鈻矨BM鈭絉T鈻矼CN 2銆(1)BM=X锛岄偅涔圕M=BC-BM=4-X 鈭礡T鈻矨BM鈭絉T鈻矼CN 鈭碅B/CM=BM/CN 4/(4-X)=X/CN CN=(4-X)X/4 鈭磞=...
绛旓細(1) B(3, 0), 0 = 9a - 6a + b, b = -3a y = ax² - 2ax - 3a = a(x + 1)(x - 3)A(-1, 0)OB = OC = 3锛 C(0, -3), -3 = a(0 + 1)(0 - 3) = -3a, a = 1 y = x² - 2x - 3 (2)D(d, d² - 2d - 3), E((d -...
绛旓細鑻ノ擜BC涓虹瓑鑵颁笁瑙掑舰锛岋紝濡傛灉a=b锛岄偅涔堟柟绋媥²-(c+2)x+2(c+1)=0 鍙湁涓涓В (c+2)²=4脳2(c+1) c=2锛2鈭2 a=b=锛坈+2锛/2 = 2+鈭2 S=0.5锛圴1+ V2) S=3(V1-V2)0.5V1+0.5V2=3V1-3V2 V1/V2 =3.5/2.5 =1.4 ...
绛旓細鍥犱负cosA=3/10锛孉B=5锛屾墍浠O=1.5锛屼粠鑰孋O=1.5锛屼粠鑰孊C=5锛屽洜涓篗N骞宠浜嶣C锛屾墍浠N/5=锛3-x/2)/3,MN=5/3*(3-x/2)=4/3*x x=30/13,AE=9/13 鎵浠E/5=9/13/3锛孌E=15/13 锛3锛夋垜瀹炲湪涓嶇煡閬撲綘鐨凢鏄摢閲屾潵鐨勶紝鎵浠ユ病娉曞仛锛屼綘杩樻槸閲嶆柊琛ュ厖涓涓棰樼洰鍚 甯屾湜瀵逛綘鏈夊府鍔 ...
绛旓細淇婄嫾鐚庤嫳鍥㈤槦涓烘偍瑙ｇ瓟 鈭礒F//AB锛孌E//AC锛屸埓鍥涜竟褰DEF鏄钩琛屽洓杈瑰舰锛屸埖AD=AF锛屸埓骞宠鍥涜竟褰DEF鏄彵褰紝璁続D=DE=EF=EF=X锛屸埖EF//AB锛孌E//AC锛屸埓螖ABC鈭轿擠BE锛屸埓AB/BD=AC/DE锛6/BD=4/DE锛3X=2BD锛屽張AB=BD+AD=BD+X=12锛屸埓3X=2(12-X)锛孹=14/5锛屽嵆EF=24/5銆
绛旓細瑙ｏ細鈶碆(0,1),璁綜(x,Y),鎹鎰忓緱鈭燘AC锛90掳锛屽垯鐢变袱鐐归棿鐨勮窛绂诲叕寮忓拰鍕捐偂瀹氱悊寰 |BC|^2=|AB|^2+|AC|^2,x^2+(y-1)^2=5+(x-2)^2+y^2锛屽寲绠寰椼y=2x-4 鈶 鍙堢偣C鍦ㄦ姏鐗╃嚎涓婏紝鏁厃=1/4x^2-x+1銆鈶 鈶犫憽鑱旂珛鏂圭▼缁勮В寰梮1=2,y1=0,锛堣垗锛夛紝x2=10,y2=16锛屼粠鑰屽緱...
绛旓細1.铔嬬硶搴楀埗浣滀袱绉嶅渾褰㈣泲绯曪紝涓绉嶅崐寰勬槸15CM锛屼竴绉嶅崐寰勬槸30CM锛岃嫢鍗婂緞鏄15CM鐨勮泲绯曞涓や釜浜哄悆锛屽崐寰勬槸30CM鐨勮泲绯曞澶氬皯浜哄悆锛燂紙楂樺害鐩稿悓锛夊崐寰勬瘮鏄細30锛15=2锛1 鍒欓潰绉瘮鏄細4锛1 閭ｄ箞30鍘樼背鐨勮兘澶燂細2*4=8浜哄悆 2.鍦ㄤ竴寮犲鍗板嚭鏉ョ殑绾镐笂锛屼竴澶氳竟褰㈢殑涓鏉¤竟鐢卞師鍥句腑鐨2CM鍙樻垚浜6CM锛岃繖娆″鍗...
绛旓細鏁呰屽瓨鍦‵鐐规弧瓒抽鎰忥紝鍏跺潗鏍囦负(2,-3)鈶涓篈B涓嬫柟鎶涚墿绾夸笂鐨勪竴涓姩鐐癸紝瑕佷娇寰桭AB鐨勯潰绉渶澶э紝灏辨槸瑕佹眰鍑篎鍒扮洿绾緼B璺濈鏈杩滅殑鐐广傚皢鐩寸嚎AB鍚戜笅鏂瑰钩绉伙紝瓒婂悜涓嬪钩绉伙紝涓ゆ潯鐩寸嚎璺濈瓒婅繙锛屽钩绉诲悗鐨勭洿绾緼'B'涓庢姏鐗╃嚎鍏堟湁涓や釜浜ょ偣锛岀劧鍚庝竴涓氦鐐癸紙鐩稿垏锛夛紝鏈鍚庣浉绂伙紝鏄剧劧锛屽綋鐩寸嚎A'B'涓庢姏鐗╃嚎鐩稿垏鐨...
