2019-2020學(xué)年廣州市番禺區(qū)八年級(jí)上冊(cè)期末考試數(shù)學(xué)試題有答案-名師版

2019-2020/r/n學(xué)年第一學(xué)期八年級(jí)期末測(cè)試題/r/n數(shù)學(xué)科/r/n【試卷說(shuō)明】/r/n1/r/n．本試卷共/r/n4/r/n頁(yè),全卷滿分/r/n100/r/n分，考試時(shí)間為/r/n120/r/n分鐘.考生應(yīng)將答案全部（涂）寫/r/n

/r/n在答題卡相應(yīng)位置上，寫在本試卷上無(wú)效.考試時(shí)允許使用計(jì)算器；/r/n2/r/n．答題前考生務(wù)必將自己的姓名、準(zhǔn)考證號(hào)等填（涂）寫到答題卡的相應(yīng)位置上；/r/n3/r/n.作圖必須用/r/n2B/r/n鉛筆，并請(qǐng)加黑加粗，描寫清楚./r/n一、選擇題（本大題共/r/n10/r/n小題，每小題/r/n2/r/n分，滿分/r/n20/r/n分.在每小題給出的四個(gè)選項(xiàng)中，只有一項(xiàng)是符合題目要求的.）/r/n1./r/n下列交通標(biāo)志是軸對(duì)稱圖形的是（探）/r/n?/r/nD/r/n）/r/n2./r/n下列運(yùn)算中正確的是（探（/r/n尸/r/n）/r/n（A）/r/na/r/n2/r/n-/r/na/r/n3/r/n=/r/na/r/n5/r/n（b）/r/nC2）/r/n二/r/na/r/n5/r/n3./r/n下列長(zhǎng)度的三條線段能組成三角形的是/r/nA）/r/n2,3,5/r/nB）/r/n7,4,2/r/n4./r/n下列各分式中/r/nx/r/n2/r/n+/r/ny/r/n2/r/n

/r/n（A）/r/nx/r/n+/r/ny/r/n是最簡(jiǎn)分式的是（探）/r/n?/r/n

/r/nx/r/nD/r/n）/r/n2./r/n下列運(yùn)算中正確的是（探（/r/n尸/r/n）/r/n（A）/r/na/r/n2/r/n-/r/na/r/n3/r/n=/r/na/r/n5/r/n（b）/r/nC2）/r/n二/r/na/r/n5/r/n3./r/n下列長(zhǎng)度的三條線段能組成三角形的是/r/nA）/r/n2,3,5/r/nB）/r/n7,4,2/r/n4./r/n下列各分式中/r/nx/r/n2/r/n+/r/ny/r/n2/r/n

/r/n（A）/r/nx/r/n+/r/ny/r/n是最簡(jiǎn)分式的是（探）/r/n?/r/n

/r/nx/r/n2/r/n-/r/ny/r/n2/r/n（B）/r/nx/r/n+/r/ny/r/n5./r/n在平面直角坐標(biāo)系/r/nxOy/r/n中，點(diǎn)/r/nP/r/n（/r/n2,/r/n1）/r/n6./r/n）/r/n已知圖中的兩個(gè)三角形全等，則/r/nZ1/r/n等于/r/nA）/r/n72°/r/n（B）/r/nC）/r/n50°/r/n（D）/r/nA）（－2/r/n，0）/r/n（/r/nB）（/r/n－2，1/r/n（/r/nC/r/n）/r/n※）./r/na/r/n6/r/n一/r/na/r/n2/r/n=/r/na/r/n3/r/n（D）/r/na/r/n5/r/n+/r/na/r/n5/r/n=/r/n2/r/n3,4,8/r/n（D）/r/n3,3,4/r/nx/r/n2/r/n+/r/nx/r/n（D）/r/n竺/r/nx/r/ny/r/ny/r/n2/r/n軸對(duì)稱的點(diǎn)的坐標(biāo)是/r/n（※）/r/n./r/n（－2，－1）/r/n（D）/r/n（2，－1）/r/nC）/r/n※）./r/nC）/r/nC）/r/n關(guān)于/r/ny/r/n7./r/n若分式豈的值為零,/r/nA）/r/n1/r/nB）/r/n8./r/n60°/r/n58°/r/n則/r/nx/r/n的值為（探）/r/n./r/n-/r/n1/r/nC）/r/n0/r/n第/r/n6/r/n題/r/nD）/r/n±/r/n1/r/n已知等腰三角形的一邊長(zhǎng)為/r/n4/r/n，另一邊長(zhǎng)為/r/n8/r/nA）/r/n12/r/n（/r/nB）/r/n16/r/n則它的周長(zhǎng)是/r/nC）/r/n20/r/n※）./r/n（/r/nD/r/n）/r/n16/r/n或/r/n20/r/n9./r/n如果/r/nx/r/n2/r/n+/r/n2/r/nmx/r/n+/r/n9/r/n是一個(gè)完全平方式，則/r/nm/r/n的值是（探）/r/n./r/n9./r/n（D）/r/n±/r/n6/r/nA）/r/n3/r/n（/r/nB）/r/n±/r/n3/r/n（/r/n（D）/r/n±/r/n6/r/n如圖①是長(zhǎng)方形紙帶，/r/nZ/r/nDEF/r/n二/r/na/r/n,將紙帶沿/r/nEF/r/n折疊成圖②，再沿/r/nBF/r/n折疊成圖③，則圖③中的/r/nZ/r/nCFE/r/n的度數(shù)是（探）/r/n./r/n第/r/n10/r/n題/r/n

/r/n圖①/r/n圖②/r/n圖③/r/n圖①/r/n圖②/r/n圖③/r/n(A)/r/n2/r/na/r/n(B)/r/n90/r/n°+/r/n2/r/na/r/n(C)/r/n180/r/n°—/r/n2/r/na/r/n(D)/r/n180/r/n°—/r/n3/r/na/r/n二、填空題(共/r/n6/r/n題，每題/r/n2/r/n分，共/r/n12/r/n分.)/r/n2019/r/n年，我國(guó)上海和安徽首先發(fā)現(xiàn)/r/n“H7N9/r/n”新型禽流感病毒，此病毒顆粒呈多邊形，其中球形病毒的最大直徑為/r/n0.00000012/r/n米，這一直徑用科學(xué)計(jì)數(shù)法表示為^米./r/nx/r/n—/r/n1/r/n若分式有意義，則/r/nx/r/n的取值范圍是/r/n探/r/n./r/nx/r/n+/r/n1/r/n因式分解：/r/nx/r/n2/r/n—/r/ny/r/n2/r/n=_^_/r/n./r/n3x/r/nx/r/n+/r/n4/r/n計(jì)算：/r/n+/r/n的結(jié)果是/r/n探/r/n./r/nx/r/n—/r/n2/r/n2/r/n—/r/nx/r/n已知一個(gè)多邊形的各內(nèi)角都等于/r/n120/r/n°/r/n，/r/n那么它是/r/n探/r/n邊形./r/n已知等腰三角形的底角是/r/n15/r/n°/r/n,腰長(zhǎng)是/r/n8/r/ncm/r/n，/r/n則其腰上的高是/r/n探/r/ncm/r/n./r/n三、解答題(本大題共/r/n9/r/n小題，滿分/r/n68/r/n分.解答應(yīng)寫出文字說(shuō)明、證明過(guò)程或演算步驟/r/n./r/n)/r/n(本小題滿分6分，各題3分)/r/n分解因式：(/r/n1/r/n)/r/n3a/r/n3/r/nb/r/n2/r/n—/r/n12ab/r/n3/r/nc/r/n;/r/n(2)/r/n3/r/nx/r/n2/r/n—/r/n18/r/nxy/r/n+/r/n27/r/ny/r/n2/r/n./r/n第/r/n18/r/n題/r/n5/r/n3/r/n1/r/n2/r/n3/r/n4/r/n5/r/n-3/r/n-4/r/n-5/r/nIIIic/r/n-5-4-3-2/r/n-1/r/nO/r/n第/r/n18/r/n題/r/n5/r/n3/r/n1/r/n2/r/n3/r/n4/r/n5/r/n-3/r/n-4/r/n-5/r/nIIIic/r/n-5-4-3-2/r/n-1/r/nO/r/nC/r/nZ>l/r/nI/r/nB/r/nj/r/nI/r/n4/r/n（本小題滿分6分）/r/n如圖，有一池塘，要測(cè)池塘兩端/r/nA/r/n、/r/nB/r/n的距離，可先在平地上取一個(gè)點(diǎn)/r/nC/r/n,/r/n從點(diǎn)/r/nC/r/n不經(jīng)過(guò)池塘可以直接到達(dá)點(diǎn)/r/nA/r/n和/r/nB/r/n./r/n連接/r/nAC/r/n并延長(zhǎng)到點(diǎn)/r/nD/r/n,/r/n使/r/nCD/r/n=/r/nCA/r/n./r/n連接/r/nBC/r/n并延長(zhǎng)到點(diǎn)/r/nE/r/n,/r/n使/r/nCE/r/n=/r/nCB/r/n./r/n連接/r/nDE/r/n，/r/n那/r/n么量出/r/nDE/r/n的長(zhǎng)就是/r/nA/r/n，/r/nB/r/n的距離.為什么？/r/n（本小題滿分7分）/r/nx/r/n2/r/nx/r/n已知/r/nA/r/n二-/r/n，/r/n若/r/nA/r/n=/r/n1/r/n，/r/n求/r/nx/r/n的值./r/nx/r/n+/r/n1/r/n3x/r/n+/r/n3/r/n（本小題滿分7分）/r/n如圖所示的方格紙中，每個(gè)小方格的邊長(zhǎng)都是/r/n1/r/n點(diǎn)/r/nA/r/n（/r/n-/r/n4/r/n，/r/n1）/r/n，/r/nB/r/n（/r/n-/r/n3/r/n，/r/n3）/r/n，/r/nC/r/n（/r/n-/r/n1/r/n，/r/n2）/r/n．/r/n（/r/n1/r/n）/r/n作/r/nA/r/nABC/r/n關(guān)于/r/ny/r/n軸對(duì)稱的/r/nA/r/nA/r/n'/r/nB/r/n'/r/nC/r/n'/r/n；/r/n（/r/n2/r/n）/r/n在/r/nx/r/n軸上找出點(diǎn)/r/nP/r/n，使/r/nPA/r/n+/r/nPC/r/n最小，并直接寫出點(diǎn)/r/nP/r/n的坐標(biāo)./r/n第/r/n20/r/n題/r/n（本小題滿分/r/n8/r/n分）/r/n2/r/n（/r/n1/r/n）/r/n先化簡(jiǎn)，再求值：/r/n（/r/nx/r/n+/r/n2y）/r/n2/r/n—/r/nx（x/r/n—/r/n2y）/r/n，其中/r/nx/r/n二/r/n3/r/n，/r/ny/r/n=/r/n5/r/n；/r/n(2/r/n)/r/n計(jì)算：/r/n(a/r/n+/r/n2/r/n+/r/n-L-)/r/n^^/r/n—/r/n4/r/n2/r/n—/r/na/r/n?/r/na/r/n—/r/n3/r/nAB/r/n第/r/nAB/r/n第/r/n22/r/n題/r/n（本小題滿分8分）/r/n如圖，/r/n△/r/nABC/r/n中，/r/nZ/r/nA/r/n=Z/r/nABC/r/n,/r/nDE/r/n垂直平分/r/nBC,/r/n交/r/nBC/r/n于點(diǎn)/r/nD/r/n，交/r/nAC/r/n于點(diǎn)/r/nE/r/n./r/n（/r/n1/r/n）/r/n若/r/nAB/r/n=/r/n5/r/n,/r/nBC/r/n=/r/n8/r/n，求/r/nA/r/nABE/r/n的周長(zhǎng)；⑵若/r/nBE/r/n=/r/nBA/r/n，求/r/nZ/r/nC/r/n的度數(shù)./r/n（本小題滿分8分）/r/n如圖，在/r/nA/r/nABC/r/n中，/r/nZ/r/nABC/r/n=/r/n90/r/n。/r/n，點(diǎn)/r/nD/r/n在/r/nAC/r/n上，點(diǎn)/r/nE/r/n在/r/n厶/r/nBCD/r/n的內(nèi)部，/r/nDE/r/n平分/r/nZ/r/nBDC/r/n，/r/n且/r/nBE/r/n=/r/nCE/r/n./r/n（/r/n1/r/n）求證：/r/nBD/r/n=/r/nCD/r/n；/r/n（/r/n2/r/n）求證：點(diǎn)/r/nD/r/n是線段/r/nAC/r/n的中點(diǎn)/r/n./r/n（本小題滿分9分）/r/n甲乙兩人同時(shí)同地沿同一路線開(kāi)始攀登一座/r/n600/r/n米高的山，甲的攀登速度是乙的/r/n1.2/r/n倍，他比乙早/r/n20/r/n分鐘到達(dá)頂峰/r/n./r/n甲乙兩人的攀登速度各是多少？如果山高為/r/nh/r/n米，甲的攀登速度是乙的/r/nm/r/n倍，并比乙早/r/nt/r/n分鐘到達(dá)頂峰，則兩人的攀登速度各是多少？/r/n（本小題滿分9分）/r/n如圖，在/r/nA/r/nABC/r/n中，/r/nZ/r/nABC/r/n=/r/n45/r/n。/r/n，點(diǎn)/r/nP/r/n為邊/r/nBC/r/n上一點(diǎn)，且/r/nZ/r/nPAB/r/n=/r/n15/r/n。/r/n，點(diǎn)/r/nC/r/n關(guān)于直線/r/nPA/r/n的對(duì)稱點(diǎn)為/r/nD/r/n，連接/r/nBD,/r/n又/r/nK/r/nAPC/r/n的/r/nPC/r/n邊上的高為/r/nAH/r/n./r/n1/r/n)判斷直線/r/nBD/r/n，/r/nAH/r/n是否平行？并說(shuō)明理由/r/n(2/r/n)證明：/r/nZ/r/nBAP/r/n=ZCAH/r/n./r/n第/r/n25/r/n題/r/n2019-2020/r/n學(xué)年第一學(xué)期八年級(jí)數(shù)學(xué)科期末抽測(cè)試題/r/n

/r/n參考答案及評(píng)分說(shuō)明/r/n、選擇題(本大題共/r/n10/r/n小題，每小題/r/n2/r/n分，滿分/r/n20/r/n分)/r/n11./r/n1.2/r/nX/r/n10/r/n-/r/n7/r/n；12./r/nx1/r/n；/r/n13./r/n(/r/nx/r/n+/r/ny/r/n)(/r/nx/r/n—/r/ny/r/n)/r/n；/r/n14./r/n2/r/n；/r/n15./r/n六邊形；/r/n16./r/n4/r/n./r/n［評(píng)卷說(shuō)明】/r/n1．在評(píng)卷過(guò)程中做到“三統(tǒng)一”：評(píng)卷標(biāo)準(zhǔn)統(tǒng)一，給分有理、扣分有據(jù)，始終如一；掌握標(biāo)準(zhǔn)統(tǒng)一，寬嚴(yán)適度，確保評(píng)分的客觀性、公正性、準(zhǔn)確性./r/n2．如果考生的解法與下面提供的參考解答不同，凡正確的，一律記滿分；若某一步出現(xiàn)錯(cuò)誤，則可參照該題的評(píng)分意見(jiàn)進(jìn)行評(píng)分./r/n3.評(píng)卷時(shí)不要因解答中出現(xiàn)錯(cuò)誤而中斷對(duì)該題的評(píng)閱，當(dāng)解答中某一步出現(xiàn)錯(cuò)誤，影響了后繼部分，但該步后的解答未改變這一道題的內(nèi)容和難度，在未發(fā)生新的錯(cuò)誤前，可視影響的程度決定后面部分的記分，這時(shí)原則上不應(yīng)超過(guò)后面部分應(yīng)給分?jǐn)?shù)之半；如有嚴(yán)重概念性錯(cuò)誤，就不記分，在一道題解答過(guò)程中，對(duì)發(fā)生第二次錯(cuò)誤起的部分，不記分./r/n三、解答題(本大題共/r/n9/r/n小題，滿分/r/n68/r/n分．解答應(yīng)寫出文字說(shuō)明、證明過(guò)程或演算步驟．)/r/n（本小題滿分6分，各題3分）/r/n解/r/n：（/r/n1/r/n）/r/n3ab/r/n-/r/n12ab/r/ns/r/nc/r/n=/r/n3ab/r/n2/r/n（/r/na/r/n2/r/n—/r/n4b/r/n2/r/nc/r/n）/r/n./r/n（/r/n3/r/n分）/r/n（/r/n2/r/n）/r/n3/r/nx/r/n2/r/n—/r/n18/r/nxy/r/n+/r/n27/r/ny/r/n2/r/n=/r/n3（/r/nx/r/n2/r/n—/r/n6/r/nxy/r/n+/r/n9/r/ny/r/n2/r/n）/r/n（/r/n1/r/n分）/r/n=/r/n（/r/n3/r/nx/r/n+3/r/ny/r/n）/r/n2/r/n./r/n…………（/r/n3/r/n分）/r/n【評(píng)卷說(shuō)明】/r/n1．在評(píng)卷過(guò)程中做到“三統(tǒng)一”：評(píng)卷標(biāo)準(zhǔn)統(tǒng)一，給分有理、扣分有據(jù)，始終如一；掌握標(biāo)準(zhǔn)統(tǒng)一，寬嚴(yán)適度，確保評(píng)分的客觀性、公正性、準(zhǔn)確性./r/n2．如果考生的解法與下面提供的參考解答不同，凡正確的，一律記滿分；若某一步出現(xiàn)錯(cuò)誤，則可參照該題的評(píng)分意見(jiàn)進(jìn)行評(píng)分./r/n3.評(píng)卷時(shí)不要因解答中出現(xiàn)錯(cuò)誤而中斷對(duì)該題的評(píng)閱，當(dāng)解答中某一步出現(xiàn)錯(cuò)誤，影響了后繼部分，但該步后的解答未改變這一道題的內(nèi)容和難度，在未發(fā)生新的錯(cuò)誤前，可視影響的程度決定后面部分的記分，這時(shí)原則上不應(yīng)超過(guò)后面部分應(yīng)給分?jǐn)?shù)之半；如有嚴(yán)重概念性錯(cuò)誤，就不記分，在一/r/n

/r/n道題解答過(guò)程中，對(duì)發(fā)生第二次錯(cuò)誤起的部分，不記分./r/n（本小題滿分6分）/r/n如圖，有一池塘，要測(cè)池塘兩端/r/nA/r/n、/r/nB/r/n的距離，可先在平地上取一個(gè)點(diǎn)/r/nC/r/n,/r/n從點(diǎn)/r/nC/r/n不經(jīng)過(guò)池塘可以直接到達(dá)點(diǎn)/r/nA/r/n和/r/nB/r/n./r/n連接/r/nAC/r/n并延長(zhǎng)到點(diǎn)/r/nD/r/n,/r/n使/r/nCD/r/n=/r/nCA/r/n./r/n連接/r/nBC/r/n并延長(zhǎng)到點(diǎn)/r/nE/r/n,/r/n使/r/nCE/r/n=/r/nCB/r/n./r/n連接/r/nDE/r/n，/r/n那/r/n么量出/r/nDE/r/n的長(zhǎng)就是/r/nA/r/n，/r/nB/r/n的距離.為什么？/r/n解：連接/r/nAB/r/n，由題意：/r/n在厶/r/nACB/r/n與/r/n△/r/nDCE/r/n中，/r/nCA/r/n二/r/nCD/r/n,/r/nTOC\o"1-5"\h\z/r/n/r/n</r/n上/r/nACB/r/n—上/r/nDCE/r/n,/r/n（/r/n3/r/n分）/r/nCB/r/n—/r/nCE/r/n,/r/n.口/r/nACB/r/n今口/r/nDCECSAS/r/n）/r/n./r/n（/r/n4/r/n分）/r/nAB/r/n—/r/nED/r/n，/r/n即/r/nED/r/n的長(zhǎng)就是/r/nAB/r/n的距離./r/n（/r/n6/r/n分）/r/n【評(píng)卷說(shuō)明】/r/n1．在評(píng)卷過(guò)程中做到“三統(tǒng)一”：評(píng)卷標(biāo)準(zhǔn)統(tǒng)一，給分有理、扣分有據(jù)，始終如一；掌握標(biāo)準(zhǔn)統(tǒng)一，寬嚴(yán)適度，確保評(píng)分的客觀性、公正性、準(zhǔn)確性./r/n2．如果考生的解法與下面提供的參考解答不同，凡正確的，一律記滿分；若某一步出現(xiàn)錯(cuò)誤，則可參照該題的評(píng)分意見(jiàn)進(jìn)行評(píng)分./r/n3.評(píng)卷時(shí)不要因解答中出現(xiàn)錯(cuò)誤而中斷對(duì)該題的評(píng)閱，當(dāng)解答中某一步出現(xiàn)錯(cuò)誤，影響了后繼部分，但該步后的解答未改變這一道題的內(nèi)容和難度，在未發(fā)生新的錯(cuò)誤前，可視影響的程度決定后面部分的記分，這時(shí)原則上不應(yīng)超過(guò)后面部分應(yīng)給分?jǐn)?shù)之半；如有嚴(yán)重概念性錯(cuò)誤，就不記分，在一道題解答過(guò)程中，對(duì)發(fā)生第二次錯(cuò)誤起的部分，不記分./r/n（本小題滿分7分）/r/nx/r/n2/r/nx/r/n已知/r/nA/r/n—/r/n不/r/n1/r/n-/r/n3/r/nX/r/n7/r/n3/r/n'/r/n若/r/nA/r/n—/r/n1/r/n，/r/n求/r/nx/r/n的值./r/n2/r/n分）/r/n（/r/n2/r/n分）/r/n（/r/n4/r/n分）/r/n分）/r/n分）/r/n（/r/n7/r/n分）/r/n兩邊同時(shí)乘以/r/n3（/r/nx/r/n+/r/n1）/r/n得：/r/n3/r/nx/r/n-/r/n2/r/nx/r/n—/r/n3/r/nx/r/n+/r/n3/r/n，/r/n3/r/n2x=/r/n—/r/n3/r/n即/r/nx/r/n——/r/n—/r/n./r/n2/r/n3/r/n經(jīng)檢驗(yàn)，/r/nx/r/n—/r/n-/r/n—/r/n是分式方程的解,/r/n乙/r/n3/r/nx/r/n———./r/n2/r/n【評(píng)卷說(shuō)明】/r/n1．在評(píng)卷過(guò)程中做到“三統(tǒng)一”：評(píng)卷標(biāo)準(zhǔn)統(tǒng)一，給分有理、扣分有據(jù)，始終如一掌握標(biāo)準(zhǔn)統(tǒng)一，寬嚴(yán)適度，確保評(píng)分的客觀性、公正性、準(zhǔn)確性./r/n

/r/n2．如果考生的解法與下面提供的參考解答不同，凡正確的，一律記滿分；若某一步出現(xiàn)錯(cuò)誤，則可參照該題的評(píng)分意見(jiàn)進(jìn)行評(píng)分./r/n3.評(píng)卷時(shí)不要因解答中出現(xiàn)錯(cuò)誤而中斷對(duì)該題的評(píng)閱，當(dāng)解答中某一步出現(xiàn)錯(cuò)誤，影響了后繼部分，但該步后的解答未改變這一道題的內(nèi)容和難度，在未發(fā)生新的錯(cuò)誤前，可視影響的程度決定后面部分的記分，這時(shí)原則上不應(yīng)超過(guò)后面部分應(yīng)給分?jǐn)?shù)之半；如有嚴(yán)重概念性錯(cuò)誤，就不記分，在一道題解答過(guò)程中，對(duì)發(fā)生第二次錯(cuò)誤起的部分，不記分./r/n5/r/nI/r/nI/r/n3/r/nI/r/nI/r/nI/r/n1/r/n2/r/n3/r/n4/r/n5/r/nr/r/n-2/r/n-3/r/nI/r/nI/r/n-4/r/nI/r/nI/r/nI/r/nII/r/n-/r/n-/r/nj/r/n一」/r/ni__i/r/n-5-4-3-2-1/r/n0/r/nI/r/nI/r/nI/r/n第/r/n20/r/n題/r/n(本小題滿分7分)/r/n如圖所示的方格紙中，每個(gè)小方格的邊長(zhǎng)都是/r/n1/r/n點(diǎn)/r/nA/r/n(/r/n—/r/n5/r/nI/r/nI/r/n3/r/nI/r/nI/r/nI/r/n1/r/n2/r/n3/r/n4/r/n5/r/nr/r/n-2/r/n-3/r/nI/r/nI/r/n-4/r/nI/r/nI/r/nI/r/nII/r/n-/r/n-/r/nj/r/n一」/r/ni__i/r/n-5-4-3-2-1/r/n0/r/nI/r/nI/r/nI/r/n第/r/n20/r/n題/r/n作/r/nA/r/nABC/r/n關(guān)于/r/ny/r/n軸的/r/nA/r/nA/r/n'/r/nB/r/n'/r/nC/r/n'/r/n；/r/n在/r/nx/r/n軸上找出點(diǎn)/r/nP/r/n，使/r/nPA/r/n+/r/nPC/r/n最小，并直接寫出點(diǎn)/r/nP/r/n的坐標(biāo)./r/n解：(1)/r/n如圖.……(/r/n3/r/n分)/r/n(2)/r/n如圖,…………(/r/n5/r/n分)/r/nP/r/n(/r/n-/r/n3/r/n,/r/n0)./r/n…………(/r/n7/r/n分)/r/n5/r/nB/r/n4/r/n3/r/n\/r/nA/r/n二/r/n2/r/nC/r/n//r/n1/r/nA/r/n5/r/n-/r/n3/r/n-/r/n2/r/n一/r/n1/r/n0/r/n-/r/n//r/n2:/r/n3/r/nL/r/n5/r/nA/r/n-1/r/n-2/r/n-3/r/n-4/r/n-5/r/n【評(píng)卷說(shuō)明】/r/n1.在評(píng)卷過(guò)程中做到“三統(tǒng)一”：評(píng)卷標(biāo)準(zhǔn)統(tǒng)一,給分有理、扣分有據(jù),始終如一；掌握標(biāo)準(zhǔn)統(tǒng)一,寬嚴(yán)適度,確保評(píng)分的客觀性、公正性、準(zhǔn)確性./r/n如果考生的解法與下面提供的參考解答不同,凡正確的,一律記滿分；若某一步出現(xiàn)錯(cuò)誤,則可參照該題的評(píng)分意見(jiàn)進(jìn)行評(píng)分./r/n評(píng)卷時(shí)不要因解答中出現(xiàn)錯(cuò)誤而中斷對(duì)該題的評(píng)閱,當(dāng)解答中某一步出現(xiàn)錯(cuò)誤,影響了后繼部分,但該步后的解答未改變這一道題的內(nèi)容和難度,在未發(fā)生新的錯(cuò)誤前,可視影響的程度決定后面部分的記分,這時(shí)原則上不應(yīng)超過(guò)后面部分應(yīng)給分?jǐn)?shù)之半；如有嚴(yán)重概念性錯(cuò)誤,就不記分,在一道題解答過(guò)程中,對(duì)發(fā)生第二次錯(cuò)誤起的部分,不記分./r/n(本小題滿分/r/n8/r/n分)/r/n2/r/n(/r/ni/r/n)/r/n先化簡(jiǎn)，再求值：/r/n(/r/nx/r/n+/r/n2/r/ny/r/n)/r/n2/r/n—/r/nx/r/n(/r/nx/r/n—/r/n2/r/ny/r/n)/r/n，其中/r/nx/r/n=/r/n3/r/n，/r/ny/r/n=/r/n5/r/n；/r/n

/r/n（2/r/n）/r/n計(jì)算：/r/n（a/r/n+/r/n2/r/n+旦/r/n）/r/n空/r/n4/r/n解：（/r/n1/r/n（2/r/n）/r/n計(jì)算：/r/n（a/r/n+/r/n2/r/n+旦/r/n）/r/n空/r/n4/r/n解：（/r/n1/r/n）/r/n（x/r/n+/r/n2y/r/n）/r/n2/r/n一/r/nx（x/r/n一/r/n2y）=x/r/n2/r/n+/r/n4xy/r/n+/r/n4y/r/n2/r/n一/r/nx/r/n2/r/n+/r/n2xy/r/n2/r/n分）/r/n=6/r/nxy/r/n+/r/n4/r/ny/r/n2/r/n3/r/n分）/r/nx/r/n二-/r/n,/r/ny/r/n=/r/n5,/r/n3/r/n2/r/n6/r/nxy/r/n+/r/n4/r/ny/r/n2/r/n=6/r/nx/r/n—/r/nx/r/n5+4/r/nx/r/n5/r/n2/r/n=125/r/n./r/n4/r/n分）/r/n2a/r/n一/r/n4/r/n4/r/n―/r/na/r/n2/r/n+/r/n52（2/r/n―/r/na/r/n）/r/n5/r/n/r/n（2）/r/n（/r/na/r/n+/r/n2+/r/n-/r/n）口/r/n—/r/n=~2/r/nx/r/n_—/r/n/r/n2/r/n一/r/na/r/n」/r/na/r/n一/r/n3/r/n2/r/n—/r/na/r/n3/r/n—/r/na/r/n/r/n（/r/n3+/r/na/r/n）（3/r/n一/r/na/r/n）/r/n2/r/n=/r/nx/r/n——/r/n3/r/n一/r/na/r/n6/r/n分）/r/n7/r/n分）/r/n8/r/n分）/r/n【評(píng)卷說(shuō)明】/r/n1.在評(píng)卷過(guò)程中做到“三統(tǒng)一”：評(píng)卷標(biāo)準(zhǔn)統(tǒng)一，給分有理、扣分有據(jù)，始終如一；掌握標(biāo)準(zhǔn)統(tǒng)一，寬嚴(yán)適度，確保評(píng)分的客觀性、公正性、準(zhǔn)確性./r/n如果考生的解法與下面提供的參考解答不同，凡正確的，一律記滿分；若某一步出現(xiàn)錯(cuò)誤，則可參照該題的評(píng)分意見(jiàn)進(jìn)行評(píng)分./r/n評(píng)卷時(shí)不要因解答中出現(xiàn)錯(cuò)誤而中斷對(duì)該題的評(píng)閱，當(dāng)解答中某一步出現(xiàn)錯(cuò)誤，影響了后繼部分，但該步后的解答未改變這一道題的內(nèi)容和難度，在未發(fā)生新的錯(cuò)誤前，可視影響的程度決定后面部分的記分，這時(shí)原則上不應(yīng)超過(guò)后面部分應(yīng)給分?jǐn)?shù)之半；如有嚴(yán)重概念性錯(cuò)誤，就不記分，在一道題解答過(guò)程中，對(duì)發(fā)生第二次錯(cuò)誤起的部分，不記分./r/n（本小題滿分8分）/r/n如圖，/r/n△/r/nABC/r/n中，/r/nZ/r/nA/r/n=ZABC/r/n,/r/nDE/r/n垂直平分/r/nBC,/r/nAB/r/n第/r/n22/r/n題/r/n（/r/n2/r/n分）/r/n交/r/nBC/r/n于點(diǎn)/r/nD/r/n，交/r/nAB/r/n第/r/n22/r/n題/r/n（/r/n2/r/n分）/r/n（/r/n1/r/n）/r/n若/r/nAB/r/n=/r/n5/r/n,/r/nBC/r/n=/r/n8/r/n，求/r/nA/r/nABE/r/n的周長(zhǎng);/r/n（/r/n2/r/n）/r/n若/r/nB/r/nE/r/n=/r/nBA/r/n，求/r/nZ/r/nC/r/n的度數(shù)./r/n解：/r/n⑴/r/nTA/r/nABC/r/n中，/r/nZ/r/nA/r/n=Z/r/nABC/r/n，/r/n./r/nAC/r/n=/r/nBC/r/n=/r/n8./r/n………………（/r/n1/r/n分）/r/nT/r/nde/r/n垂直平分/r/nBC/r/n，/r/n./r/nEB/r/n=/r/nEC/r/n./r/n丈:/r/nAB/r/n=/r/n5/r/n,??△/r/nABE/r/n的周長(zhǎng)為:/r/n

/r/nTOC\o"1-5"\h\z/r/nAB/r/n+/r/nAE/r/n+/r/nEB/r/n二/r/nAB/r/n+/r/n（/r/nAE/r/n+/r/nEC/r/n）/r/n二/r/nAB/r/n+/r/nAC/r/n二/r/n5/r/n+/r/n8/r/n二/r/n13/r/n./r/n（/r/n4/r/n分）/r/n⑵/r/n".?EB/r/n=/r/nEC/r/n,/r/n???Z/r/nC/r/n二/r/nZ/r/nEBC/r/n./r/nT/r/nZ/r/nAEB/r/n二/r/nZ/r/nC/r/n+Z/r/nEBC/r/n,/r/n?-/r/nZ/r/nAEB/r/n=/r/n2/r/nZ/r/nC./r/n（/r/n5/r/n分）/r/nTBE/r/n二/r/nBA/r/n,/r/n?-/r/nZ/r/nAEB/r/n=/r/nZA./r/n又/r/nAC/r/n=/r/nBC/r/n,/r/n?-/r/nZ/r/nCBA/r/n二/r/nZ/r/nA/r/n二/r/n2/r/nZ/r/nC./r/n（/r/n6/r/n分）/r/nT/r/nZ/r/nC/r/n+/r/nZ/r/nA/r/n+Z/r/nCBA/r/n=/r/n180/r/n。/r/n，/r/n（/r/n7/r/n分）/r/n?-/r/n5/r/nZ/r/nC/r/n二/r/n180/r/n。/r/n./r/n?/r/nZ/r/nC/r/n=/r/n36/r/n。./r/n（/r/n8/r/n分）/r/n【評(píng)卷說(shuō)明】/r/n1/r/n．在評(píng)卷過(guò)程中做到“三統(tǒng)一”：評(píng)卷標(biāo)準(zhǔn)統(tǒng)一，給分有理、扣分有據(jù)，始終如一；掌握標(biāo)準(zhǔn)統(tǒng)一，寬嚴(yán)適度，確保評(píng)分的客觀性、公正性、準(zhǔn)確性./r/n2/r/n．如果考生的解法與下面提供的參考解答不同，凡正確的，一律記滿分；若某一步出現(xiàn)錯(cuò)誤，則可參照該題的評(píng)分意見(jiàn)進(jìn)行評(píng)分./r/n3./r/n評(píng)卷時(shí)不要因解答中出現(xiàn)錯(cuò)誤而中斷對(duì)該題的評(píng)閱，當(dāng)解答中某一步出現(xiàn)錯(cuò)誤，影響了后繼部分，但該步后的解答未改變這一道題的內(nèi)容和難度，在未發(fā)生新的錯(cuò)誤前，可視影響的程度決定后面部分的記分，這時(shí)原則上不應(yīng)超過(guò)后面部分應(yīng)給分?jǐn)?shù)之半；如有嚴(yán)重概念性錯(cuò)誤，就不記分，在一道題解答過(guò)程中，對(duì)發(fā)生第二次錯(cuò)誤起的部分，不記分./r/n（本小題滿分8分）/r/n如圖，在/r/n△/r/nABC/r/n中，/r/nZABC/r/n=/r/n90/r/n。/r/n，點(diǎn)/r/nD/r/n在/r/nAC/r/n上，點(diǎn)/r/nE/r/n在/r/nA/r/nBCD/r/n的內(nèi)部，/r/nDE/r/n平分/r/nZBDC/r/n,/r/n且/r/nBE/r/n=/r/nCE/r/n./r/n（/r/n1/r/n）求證：/r/nBD/r/n=/r/nCD/r/n；/r/n（/r/n2/r/n）求證：點(diǎn)/r/nD/r/n是線段/r/nAC/r/n的中點(diǎn)/r/n./r/n證明：（/r/n1/r/n）/r/n過(guò)點(diǎn)/r/nE/r/n作/r/nEM/r/n丄/r/nCD/r/n于/r/nM/r/n，/r/nEN/r/n丄/r/nBD/r/n于/r/nN,/r/n■//r/nDE/r/n平分/r/nZ/r/nBDC/r/n，/r/n?/r/nEM/r/n=/r/nEN/r/n./r/n在/r/nRt/r/nA/r/nECM/r/n和/r/nRt/r/nA/r/nEBN/r/n中，/r/n在/r/nRt/r/nA/r/nECM/r/n和/r/nRt/r/nA/r/nEBN/r/n中，/r/n?-/r/nRt/r/nA/r/nECM/r/n仝/r/nRt/r/nA/r/nEBN/r/n./r/nZ/r/nMCE/r/n=Z/r/nNBE/r/n./r/n……………（/r/n3/r/n分）/r/n又:/r/nBE/r/n=/r/nCE/r/n,/r/n-/r/nZ/r/nECB/r/n=/r/nZ/r/nEBC./r/n（/r/n4/r/n分）/r/nZ/r/nDCB/r/n=/r/nZ/r/nDBC/r/n./r/nBD/r/n=/r/nCD/r/n./r/n…………（/r/n5/r/n分）/r/n（2^'/r/n△/r/nABC/r/n中，/r/nZ/r/nABC/r/n=/r/n90/r/n。/r/n，/r/n?/r/nZ/r/nDCB/r/n+Z/r/nA/r/n=/r/n90/r/n。/r/n,/r/nZ/r/nDBC/r/n+Z/r/nABD/r/n=/r/n90/r/n。/r/n./r/n7/r/n分）/r/nZ/r/nA/r/n=Z/r/nABD/r/n./r/nAD/r/n=/r/nBD/r/n./r/n7/r/n分）/r/n又：/r/nBD/r/n=/r/nCD/r/n./r/nAD/r/n二/r/nCD/r/n,/r/n即：點(diǎn)/r/nD/r/n是線段/r/nAC/r/n的中點(diǎn)/r/n./r/n8/r/n分）/r/n【評(píng)卷說(shuō)明】/r/n1．在評(píng)卷過(guò)程中做到“三統(tǒng)一”：評(píng)卷標(biāo)準(zhǔn)統(tǒng)一，給分有理、扣分有據(jù)，始終如一；掌握標(biāo)準(zhǔn)統(tǒng)一，寬嚴(yán)適度，確保評(píng)分的客觀性、公正性、準(zhǔn)確性./r/n2．如果考生的解法與下面提供的參考解答不同，凡正確的，一律記滿分；若某一步出現(xiàn)錯(cuò)誤，則可參照該題的評(píng)分意見(jiàn)進(jìn)行評(píng)分./r/n3.評(píng)卷時(shí)不要因解答中出現(xiàn)錯(cuò)誤而中斷對(duì)該題的評(píng)閱，當(dāng)解答中某一步出現(xiàn)錯(cuò)誤，影響了后繼部分，但該步后的解答未改變這一道題的內(nèi)容和難度，在未發(fā)生新的錯(cuò)誤前，可視影響的程度決定后面部分的記分，這時(shí)原則上不應(yīng)超過(guò)后面部分應(yīng)給分?jǐn)?shù)之半；如有嚴(yán)重概念性錯(cuò)誤，就不記分，在一道題解答過(guò)程中，對(duì)發(fā)生第二次錯(cuò)誤起的部分，不記分./r/n24.（本小題滿分9分）/r/n甲乙兩人同時(shí)同地沿同一路線開(kāi)始攀登一座/r/n600/r/n米高的山，甲的攀登速度是乙的/r/nAD/r/n二/r/nCD/r/n,/r/n即：點(diǎn)/r/nD/r/n是線段/r/nAC/r/n的中點(diǎn)/r/n./r/n8/r/n分）/r/n【評(píng)卷說(shuō)明】/r/n1．在評(píng)卷過(guò)程中做到“三統(tǒng)一”：評(píng)卷標(biāo)準(zhǔn)統(tǒng)一，給分有理、扣分有據(jù)，始終如一；掌握標(biāo)準(zhǔn)統(tǒng)一，寬嚴(yán)適度，確保評(píng)分的客觀性、公正性、準(zhǔn)確性./r/n2．如果考生的解法與下面提供的參考解答不同，凡正確的，一律記滿分；若某一步出現(xiàn)錯(cuò)誤，則可參照該題的評(píng)分意見(jiàn)進(jìn)行評(píng)分./r/n3.評(píng)卷時(shí)不要因解答中出現(xiàn)錯(cuò)誤而中斷對(duì)該題的評(píng)閱，當(dāng)解答中某一步出現(xiàn)錯(cuò)誤，影響了后繼部分，但該步后的解答未改變這一道題的內(nèi)容和難度，在未發(fā)生新的錯(cuò)誤前，可視影響的程度決定后面部分的記分，這時(shí)原則上不應(yīng)超過(guò)后面部分應(yīng)給分?jǐn)?shù)之半；如有嚴(yán)重概念性錯(cuò)誤，就不記分，在一道題解答過(guò)程中，對(duì)發(fā)生第二次錯(cuò)誤起的部分，不記分./r/n24.（本小題滿分9分）/r/n甲乙兩人同時(shí)同地沿同一路線開(kāi)始攀登一座/r/n600/r/n米高的山，甲的攀登速度是乙的/r/n1.2/r/n倍，他比乙早/r/n20/r/n分鐘到達(dá)頂峰/r/n./r/n甲乙兩人的攀登速度各是多少？如果山高為/r/nh/r/n米，甲的攀登速度是乙的/r/nm/r/n倍，并比乙早/r/nt/r/n分鐘到達(dá)頂峰，則兩人的攀登速度各是多少？/r/n解：設(shè)乙的速度為/r/nx/r/n米/時(shí),/r/n1/r/n分）/r/n則甲的速度為/r/n1.2x/r/n米/時(shí),/r/n根據(jù)題意，得：/r/n60060020/r/nx/r/n1.2/r/nx/r/n60/r/n2/r/n分）/r/n4/r/n分）/r/n方程兩邊同時(shí)乘以/r/n3/r/nx/r/n得:/r/n18/r/n°0/r/n—/r/n150/r/n0/r/n=/r/nx/r/n,/r/n即：/r/nx/r/n=/r/n300/r/n./r/n經(jīng)檢驗(yàn)，/r/nx=300/r/n是原方程的解．/r/n5/r/n分）/r/n???/r/n甲的攀登速度為/r/n360/r/n米/時(shí)，乙的速度為/r/n300/r/n米/時(shí)./r/n（/r/n6/r/n分）/r/n當(dāng)山高為/r/nh/r/n米，甲的攀登速度是乙的/r/nm/r/n倍，并比乙早/r/nt（t/r/n>/r/n0）/r/n分鐘到達(dá)頂峰時(shí)，/r/n設(shè)乙的速度為/r/ny/r/n米/時(shí)，則有:/r/nhh/r/n_/r/nt/r/nmy/r/n60/r/n7/r/n分)/r/n解此方程得：/r/ny/r/n=/r/n60/r/nhm/r/n—V/r/nmt/r/n當(dāng)/r/nm/r/n>/r/n1/r/n時(shí)，/r/ny/r/n=/r/n6/r/n叫—/r/nD/r/n是原方程的解,/r/nmt/r/n8/r/n分)/r/n當(dāng)/r/nm/r/n</r/n1/r/n時(shí)，甲不可能比乙早到達(dá)頂峰/r/n此時(shí)甲的攀登速度為/r/n60/r/nh/r/n(/r/nm/r/n—/r/n此時(shí)甲的攀登速度為/r/n60/r/nh/r/n(/r/nm/r/n—/r/n1)/r/nt/