2022-2023学年浙江省宁波市海曙区部分学校八年级（上）期中数学试卷（含解析）

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2022-2023
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ḄឋgÈ30°
Ḅ

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ḄឋஹÈ30°
Ḅ

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20AZADP=60°,PD=PA=i2,VPC=13,:.CA+PD'PC1,&.ZPDC=90°,AZAPB=ZADC=ZADP+ZPDC=f)Oa+90°=150°.ூ!௃3⚪ὃ&'©ªḄឋᐰDEFḄᑨrsឋNDEFḄᑨrsឋ-./0©ªḄឋ2⚪Ḅᐵ5.22.«¬ᓝ®=᪥°±'ᦟ³´µ¶·'+¸឵º⚪Ḅᨵᝄ¼ᦻ¾¿ÀÁᝄḄ´⚙ÄᝄÅ.LÆXL¡ÇᦻᓄᖪÊËÌᵬஹWÎÏÐÑ3lᝄÅÌᵬÏÐÑ320QWÏÐÑ310Qᐳᵨ110ᐗ^ÌᵬÏÐÑ330QÒÌWÏÐÑ320QÓÔ10ᐗ.(1)BᵬஹWÎÏÐÑ3ḄᓫÖᔜ2ØÓᐗÙ(2)3*ËÚᵬÏÐÑ3ḄᦪÛÒWÏÐÑ3ḄᦪÛḄ2ÜÝÓ10Q^ËÌÞÎÏÐÑ3Ḅßàáâã320ᐗB3*WÏÐÑ3ᨬØËÌØÓQÙூᑖ᪆௃(1)✌ᐜoᵬÏÐÑ3ḄᓫÖ2xᐗWÏÐÑ3ḄᓫÖ2yᐗ᪷⚪èজ20QᵬÏÐÑ3ḄÖ<+10QWÏÐÑ3ḄÖ<=110ᐗVঝᵬÏÐÑ330QḄÖ<+10=WÏÐÑ320QḄÖ<᪷Ûᐵéᑡ;êëᓽV(2)oWÏÐÑ3ËÌaQᵫ⚪èᐵé3XᵬÏÐÑ3ḄᦪÛ+5XWÏÐÑ3ḄᦪÛW320ᐗ᪷ᐵéᑡëᓽ.(1)oᵬÏÐÑ3ḄᓫÖ2xᐗWÏÐÑ3ḄᓫÖ2yᐗᵫ⚪èr20x+10y=110l30x+10=20y'ì=3.Iy=5hᵬÏÐÑ3ḄᓫÖ23ᐗVWÏÐÑ3ḄᓫÖ25ᐗV(2)oWÏÐÑ3ËÌ஺Qᵫ⚪è3(2a-10)+5aW320,a431í᦮ᦪï஻ñ31.

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