các bài toán cơ bản hình học lớp 8

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8 ;< = = µ ; 7 > =  Q P N M ?@         3  G AAAAAAAAAAAAAAAAAA 1 * & B!01* B!-5C01* .!D* B! B!-5C EF1 ?@ +!"#$%&'()!':* B C A D a) y x 40 0 80 0 A B C D b) y x 70 0 50 0 A D C B c) y x 65 0             4  G x 55 0 A B D C A B C D b) y x 75 0 56 0 B C A D a) y x 42 0 86 0                     G01!*    5  G D C B A   AAAAAAAAAAAAAAAAAAAAAA 1+* &' EHI*B!J01*  .!D* 01!J µ µ     =    ⇔  = =   :9K!J* EH0L* /DMLN5* EH0L * /DMLN5* +8O5PK5N5Q:!J*    6  G  EF1 ?@ 01!J/R8 N M D C B A        01!J/R8= /R/ D C B A M        +J=/R8 /801!J : µ ;  G<= 9!J $ N M C B A        GJ/801 !J-1/R/8  7  G N M C B A         <B! · ·   =  01!J O A B C D        AAAAAAAAAAAAAAAAA 1G*()*+ ,&&-.,& & E2345! :$H0L*   /D! -1MLN5 8  G   :$H0L *     !&S%! C B A I K x 10cm 8cm 8cm 50 0 50 0 C B A I K x 11cm 15cm 15cm 53 0 53 0 PBRBT K H A B C M N         9  G E2345!! :$H0L+*      :$H0LG*      /D! -1MLN5 +!"#$%&'()!* H B C D A E x 32m 24m 10 [...]... …………………………………………………………… B …………………………………………………………… P N …………………………………………………………… C D …………………………………………………………… …………………………………………………………… …………………………………………………………… …………………………………………………………… 8/ Tính x; 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Biết AB // CD // EF // GH A C E G 8cm B x …………………………………………………………… D …………………………………………………………… F 16cm y H …………………………………………………………… …………………………………………………………… …………………………………………………………… 12 Giáo viên thực hiện : Phạm Văn . *     !&S%! C B A I K x 10cm 8cm 8cm 50 0 50 0 C B A I K x 11cm 15cm 15cm 53 0 53 0 PBR BT K H A B C M N         9