(1)∵DE垂直平分AB,FG垂直平分AC,∴EB=EA,FA=FC,∴∠BAE=∠B,∠FAC=∠C,∵△ABC中,∠BAC=130°,∴∠B+∠C=50°,∴∠BAE+∠FAC=50°,∴∠EAF=∠BAC-(∠BAE+∠FAC)=80°;
(2)∵BC=18cm,∴△AEF的周长为:AE+AF+EF=BE+CF+EF=BC=18cm.
已知三角形abc中角bac等于130度bc等于18度abac的垂直平分线分别交bc于ef与aba求高手给解答
(1)∵DE垂直平分AB,FG垂直平分AC,∴EB=EA,FA=FC,∴∠BAE=∠B,∠FAC=∠C,∵△ABC中,∠BAC=130°,∴∠B+∠C=50°,∴∠BAE+∠FAC=50°,∴∠EAF=∠BAC-(∠BAE+∠FAC)=80°;
(2)∵BC=18cm,∴△AEF的周长为:AE+AF+EF=BE+CF+EF=BC=18cm.