y=x*[30+(90-x)]-60*[30+(90-x)]怎么解
问题描述:
y=x*[30+(90-x)]-60*[30+(90-x)]怎么解
答
作CM平行AB
DN平行EF
y=x*[30+(90-x)]-60*[30+(90-x)]怎么解
作CM平行AB
DN平行EF