精品解析2022年人教版初中数学七年级下册第八章二元一次方程组专题练习试题(含答案及详细解析)

经典word整理文档，仅参考，双击此处可删除页眉页脚。本资料属于网络整理，如有侵权，请联系删除，谢谢！三二3）5xy5xyxy1x21xy10y2x62xz2yxy2﹣）20x1x3xxy1y5y5y1xy为）911911xyxy9xy11yx139xy11yx1399xyxy8xyyx8xy10yx2xy得xyy4x2y）x2y4k）xy12xyk175）xy2﹣）x2x0x1x31y5y3y1y8）元元元元3x4y5kkx3yk,y）2xy2k3233x2y）8x2yx4x5x3x2121y2y2yy423xyxy5ab、3yb1xyyxy﹣+ABCDABADaa(ax(a1)y02x3y1252xy1283x342x3y2y3xxyyxx．y；；；232323232323ab、03abab、003abab；ab，mn10mn4m①mx3y12x2m，ny②16xy4x543y15xyxyA解A．xy102xBy25xyy中C1x6y1xy3D2xz2xy2﹣2xxy2﹣把1y0xxy2﹣把把把5y1xxy2﹣5y3xxy2﹣1yxy9xy．yyx8xx2xyx2yxyyyy得22+4+xyxyk+＋①x2y42xyk②xyk，k4∴xy，3∵∴xy1，k4，13∴，k43，k1xyxy5，xy1yx5，22xy330x，170y330170160，xy2﹣2xxy2﹣把y10xxy2﹣把把把y51xxy2﹣y33xxy2﹣y1xy8xyxy，80.85xyx200，y155kx3yk①3x4y5k，y2k②2x，x3y2k∵，x3y10k∴，2k10k，k2x3y2kxxxy①3x2y，8x2y②xxxy把yx3，y2yx22yx3xy23xyyx．22yx3abba115ab、a3b1xy53yb1115∴，a3b1ab∴abcaebfcggxy、xyy﹣xy∴，yx1，1yxy∴+xyABCD=ADxyxyxy和2x2y32x2yABCD=，2y3yx3yx324x，y5ADxyyyxy=+=1或1a10a10a1a1a10且a10aa(ax(a1)y0xa10且a10，；a1(a1)x(a1)y0当a1a102y0当a10a12x0或1)3x2x731y－＝①2xy5，32②x2，2把x2，y12x∴．y1231xy，2xy134①2x3y1，4x3y②xxxy把7；y33x．73y3xy8①2x3y2y②3xxy①2得4xy②3得9x④5x将y3x8y73y72x，yx232x73yxyyx∴2x73y，372，73y72x∴，．xy23，,mnmn10mn4mnmn,23235,23＞，2323235,235,=，232323235,2355,=，232303=0+3=3,0333,=，0303ab、ab＞，abab若、0ab=；ab，，mn10mn4mnmn,,n当mnmnnm即mm104,2m104,或m2m104或mm7当m0,n0,nmn,2m104,或2m4m3或m故m32xy24x