Proof: Opposite sides of parallelogram congruent | Quadrilaterals | Geometry | Khan Academy

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Proving that a figure is a parallelogram if and only if opposite sides are congruent
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[@ElizaCanezaresGamor-tr6gc]

1:1 1:20 １:２６ 3

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[@ClaireShin86]

Thanks so much!!! I had no idea what I was doing but I finally figured it out because of this video!

[@nageswararaolingineni737]

thanks for your help :)

[@thinghestings3243]

Very helpful to me.

[@gtaeducationalhub9880]

Great job

[@yashasvprajapati6851]

You'd have used CPCT (Corresponding parts of Congruent Triangles are equal).

[@williamchung683]

forgot a C CPCTC

[@snip-sniptear956]

Really awesome! Needed this for the last problem on my Proof hw assignment.

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do you go to Olympiads cause I do andd it was also the last question on my homework asiignment

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[@xXCatSithXx]

what program is he drawling in

[@hellfigter12345]

Can`t u just proof it by Rsh postulate?

[@nusaibafatima1324]

7:24 there is something else down there

[@yh2k]

but what is opposit sodes

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ez

[@Cecielii]

Uhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh can you repeat that?

[@crazymoonlight500]

; )

[@aidenmisao822]

Isn't it wrong to begin with the assumption that the opposite sides are parallel?

[@gianaperez2009]

Aiden Misao it has the hash marks so it means the sides are congruent and parallel

[@xwarrior760]

Of course not. That's the definition of a parallelogram and the fact that you're using a parallelogram is given.

[@agelikizac5655]

Thanks it realy helps me