Question

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Answer 1

1.b) ABCD romb=>m(∡A)=m(∡C)=30°
       Notam d(B,DC)=BE=> BE⊥CD=>m(∡BEC)=m(∡BED)=90°
       m(∡EBC)+m(∡BCE)+m(∡CEB)=180°=>
=>  m(∡EBC)+30°+90°=180°=>
=>  m(∡ECB)+120°=180°=>
=>  m(∡ECB)=180°-120°=>
=>  m(∡ECB)=60°
      Conform TEOREMEI 30,60,90, cateta opusa unghiului de 30° este jumatate din ipotenuza.=>BE=BC:2=>BE=36:2=>BE=18cm=>d(B,CD)=18cm
     a)  Aromb=latura x inaltimea =>Aromb=BEXCD=> Aromb=36x18=>Aromb=648cm²