Ask your own question, for FREE!
Mathematics 16 Online
OpenStudy (mathmath333):

Geometry question

OpenStudy (mathmath333):

|dw:1428072282891:dw|

OpenStudy (mathmath333):

\(\triangle ABC\) is an equilateral triangle . \(O\) os the center.\(O\) lies in the segment \(AD\). prove that \(AO:OD::2:1\)

OpenStudy (mathmath333):

\(\large \color{black}{\begin{align} AB^2=AD^2+BD^2\hspace{.33em}\\~\\ BO^2=OD^2+BD^2\hspace{.33em}\\~\\ AO=BO=r\hspace{.33em}\\~\\ \end{align}}\)

OpenStudy (rational):

how do you know triangle ABD is right triangle ?

OpenStudy (mathmath333):

|dw:1428073130913:dw|

OpenStudy (mathmath333):

|dw:1428073190473:dw|

OpenStudy (rational):

that doesnt prove angle D is right angle yet

OpenStudy (rational):

that just shows that triangle OBC is an isosceles triangle

OpenStudy (mathmath333):

we can prove that \(\large \color{black}{\begin{align} \triangle OBD \cong \triangle OCD\hspace{.33em}\\~\\ \end{align}}\)

OpenStudy (rational):

yes we need to prove that first

OpenStudy (mathmath333):

\(\large \color{black}{\begin{align} OB &\cong OC\hspace{.33em}\\~\\ \angle OBD &\cong \angle OCD \hspace{.33em}\\~\\ OD&=OD \end{align}}\)

OpenStudy (rational):

|dw:1428073451442:dw|

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!