ʱ : ڶ 人教版最全七年级数学下册全册同步练习及单元检测卷及答?- 百度文库ϿʼĶ
82ԪһηĽⷨ1
ϰ⣨5ӣ 1úxĴʽʾy:
12x+y=1
34xy-1
2жԪһη飺
1??x?3y?2,?x?3y?8.
3??x?y??5,?3x?2y?10.
2y-3x+1=0 45x10y150. 2??4x?3y?17,?y?7?5x.
4??2x?7y?8,?y?2x??3.2.
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5??2s?3t??1?xy4s?9t?8 6????1?34
??3x?2y?9
82ԪһηĽⷨ2
ϰ⣨5ӣ 1
(1)Ԫһη??x?y?1y?3Ľ_________
?x?(2)֪??2x?y?7?x?2y?8x-yֵ_______.
(3)
x2?y4?3,2x+y=___;4x+2y=_____+4y=_;10x+____=_____. (4)֪??ax?by?2cx?7y?8ĽΪ??x?3Сİc??y??2??x??2a+2b-c=_______. ?y?22 üӼз顣
(1) ??3x?y?8?3m?y?7 (2) 2n?16?2x??
?3m?n?1
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?4x?7y?7?2x?4y?15(3) ? (4) ?
8x?7y?52x?3y?1??
?3x?2y?6?4x?2y?14(5)? (6)?
2x?3y?175x?y?7??
?x?3y??20?2x?3y?8(7)? (8)?
3x?7y?1005y?7x?5??
82ԪһηĽⷨ3
ϰ⣨5ӣ 1գ
?x?y?a (1)xyķ?Ľ________.
?x?y?b?3m?2n?11?m?3?3(x?y)?2(x?y)?11 (2)֪?ĽΪ??֪
4m?3n?9n??14(x?y)?3(x?y)?9???x+y=_______;x-y=_______;x=_____;y=_____. 2ʵķз飺
?x?y?8?x?y?4(1) ? (2)?
?5x?2(x?y)??1?4x?2y??2
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?3m?2n?2?2m?3n?83? 4 ?
3m?2n??14m?5n?18??
3b?m?nm?n???12a??1???2?225? 6? m?nm?nb?a1?????1????344?4?
3֪y=kx+bx=2ʱ,y=-3;x=1ʱ,y=2.(1)kbֵ2x= -1ʱyֵ
?x?1?x?0?4??1ǹxyķax+by8Ľ⣬:a+bֵ.
?y??2?y?2?
8.3 ʵԪһη飨1
ϰ⣨5ӣ
1ijѧѧ4200ˣƻһ8%У11%ȫУѧ10%ѧУڵijУУǶˣ
2дС3Сһο֧1550֣56Сһο֧35֣35Сһο˻ٶ֣
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