已知:CD是RT△ABC斜边的高,AB=5,BC=4.求S△ABC:S△ACD:S△BCD

问题描述:

已知:CD是RT△ABC斜边的高,AB=5,BC=4.求S△ABC:S△ACD:S△BCD

角ACB为直角.AC²+BC²=AB²得:AB=3 △ABC与△ACD相识得:CD:BC=AD:AC=AC:AB=4:5 得:CD=(4/5)*3=12/5 AD=(4/5)*4=16/5 S△ACD=CD*AD/2=96/25 △ABC与△BCD相识得:CD:AC=BD:BC=BC:AB=3:5 得:CD=(3/5)*4=12...