如图,点A和点B分别在x轴y轴的正半轴上,AD平分∠BAO交y轴于D,OC⊥AB于...答:故OB=OD+DF+BF=3+2+3=8,即点B为(0,8);(2)∵EF∥AB;OC⊥AB.∴OE⊥EF,则EF=√(OF²-OE²)=4.作EM垂直OF于M,由面积关系可知:EF*OE=OF*EM,4*3=5*EM, EM=12/5.则:CE=HE=OM=√(OE²-EM²)=9/5.所以,S⊿ACE/S⊿OAE=CE/EO=(9/5)/3=3/5.(...
如图,在平面坐标系中,点A,B分别在X轴,Y轴的正半轴上,且OA=OB,另有两点...答:∵C(a,b),D(b,-a),a,b>0,∴OM=a=DN,CM=b=OD,∴△OMC≌△DNO,∴∠COM=∠ODN,OC=OD,∴∠COD=∠COM+∠DON=∠ODN+∠DON=90°,∴∠ODC=45°。(2)把△OAC绕O旋转90°至△OBC',连CC'.则OC'=OC=2,BC'=AC=3,∠COC'=90°,∴∠OCC'=45°,CC'=2√2,∴BC^2+CC'^2...