Question

如图在rt三角形abc中,角c等于90度,ac=8,bc=6,按图中所示方法将三角形bcd沿bd折叠,使点c落在边ab上的点c'处

则折痕点D到AB的距离为---------

Answer 1

解:AB=√(AC^2+BC^2)=10;BC'=BC=6,则AC'=4.
∠BC'D=∠C=90°,则∠AC'D=∠C=90°;
又∠A=∠A,故⊿AC'D∽⊿ACB,AC'/AC=AD/AB.
即:4/8=AD/10,AD=5,CD=AC-AD=3,BD=√(CD^2+BC^2)=3√5.

Answer 2

解:AB=√(AC^2+BC^2)=10;BC'=BC=6,则AC'=4.
∠BC'D=∠C=90°,则∠AC'D=∠C=90°;
又∠A=∠A,故⊿AC'D∽⊿ACB,AC'/AC=AD/AB.
即:4/8=AD/10,AD=5,CD=AC-AD=3,BD=√(CD^2+BC^2)=3√5.

Answer 3

解:AB=√(AC^2+BC^2)=10;BC'=BC=6,则AC'=4.
∠BC'D=∠C=90°,则∠AC'D=∠C=90°;
又∠A=∠A,故⊿AC'D∽⊿ACB,AC'/AC=AD/AB.
即:4/8=AD/10,AD=5,CD=AC-AD=3,BD=√(CD^2+BC^2)=3√5.