tag:blogger.com,1999:blog-6933544261975483399.post1937773588215002310..comments2024-03-26T19:10:02.918-07:00Comments on Go Geometry (Problem Solutions): Problem 378. Triangle, Incenter, Parallel to a side, Angle, CongruenceAntonio Gutierrezhttp://www.blogger.com/profile/04521650748152459860noreply@blogger.comBlogger4125tag:blogger.com,1999:blog-6933544261975483399.post-38134800574681016222015-08-25T04:07:51.652-07:002015-08-25T04:07:51.652-07:00Too easy!
Tr.s IDB & IEC are both isoceles an...Too easy!<br /><br />Tr.s IDB & IEC are both isoceles and the result follows<br /><br />Sumith Peiris<br />Moratuwa<br />Sri LankaSumith Peirishttps://www.blogger.com/profile/06211995240466447227noreply@blogger.comtag:blogger.com,1999:blog-6933544261975483399.post-31895629416460125462010-06-18T16:02:09.268-07:002010-06-18T16:02:09.268-07:00Note That:
1. Area of Triangle BIE= Area of Triang...Note That:<br />1. Area of Triangle BIE= Area of Triangle CIE ( same base and height)<br />2. Area of triangle DBE= area of Tri. BDI + area of Tri. BIE<br />3. From step 1 and 2 , Write formula of area of each triangle .we will conclude that DE=DB+CEPeter Tranhttps://www.blogger.com/profile/02320555389429344028noreply@blogger.comtag:blogger.com,1999:blog-6933544261975483399.post-51976635507608448632009-12-19T08:00:49.405-08:002009-12-19T08:00:49.405-08:00draw IQ, IT radius and IP //BD
tr IDT and IPQ are...draw IQ, IT radius and IP //BD<br /><br />tr IDT and IPQ are congrunt ( IQ=IT, angTID=ang PIQ)<br />=>DBPI is rombus<br /><br />at the same way IKCE (IK//EC),rombusc .t . e. onoreply@blogger.comtag:blogger.com,1999:blog-6933544261975483399.post-52328166005420518002009-10-30T11:11:52.645-07:002009-10-30T11:11:52.645-07:00Como DE//CB, temos que Ang(DIB) = Ang(CBI) e Ang(E...Como DE//CB, temos que Ang(DIB) = Ang(CBI) e Ang(EIC) = Ang(BCI). Vejam que I é o incentro do triângulo ABC, então CI e BI são bissetrizes dos ângulos ACB e ABC. Assim os triângulos CEI e BEI são isósceles sendo BD = DI e IE = EC. Assim, como DE = DI + IE, então DE = CD + EB ( demonstrado).Valdir Marques Faria, Colégio Visãohttp://valdirmfariagmail.comnoreply@blogger.com