在△ABC和△A1B1C1中,如果∠B=∠B1那么S△ABC/S△A1B1C1=AB·BC/A1B1·B1C1.请写

问题描述:

在△ABC和△A1B1C1中,如果∠B=∠B1那么S△ABC/S△A1B1C1=AB·BC/A1B1·B1C1.请写

∵,∠B=∠B1,∠C=∠C1∴,∠A=∠A1∴△ABC∽△A1B1C1故BC/AB=B1C1/A1B1又∵AB BC=A1B1 B1C1∴1 BC/AB=A1B1/AB B1C1/AB1 BC/AB=(1 B1C1/A1B1)×(A1B1/AB)由BC/AB=B1C1/A1B1得1 BC/AB=(1 BC/AB)×(A1B1/AB)∴A1B1/AB=1...