Geometry question
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\(\triangle ABC\) is an equilateral triangle . \(O\) os the center.\(O\) lies in the segment \(AD\). prove that \(AO:OD::2:1\)
\(\large \color{black}{\begin{align} AB^2=AD^2+BD^2\hspace{.33em}\\~\\ BO^2=OD^2+BD^2\hspace{.33em}\\~\\ AO=BO=r\hspace{.33em}\\~\\ \end{align}}\)
how do you know triangle ABD is right triangle ?
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that doesnt prove angle D is right angle yet
that just shows that triangle OBC is an isosceles triangle
we can prove that \(\large \color{black}{\begin{align} \triangle OBD \cong \triangle OCD\hspace{.33em}\\~\\ \end{align}}\)
yes we need to prove that first
\(\large \color{black}{\begin{align} OB &\cong OC\hspace{.33em}\\~\\ \angle OBD &\cong \angle OCD \hspace{.33em}\\~\\ OD&=OD \end{align}}\)
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