题目用一条长为18cm18cm18cm的细绳围成一个等腰三角形,若一边长是4cm4cm4cm,则腰长为( )A.4cm4cm4cmB.7cm7cm7cmC.4cm4cm4cm或7cm7cm7cmD.10cm10cm10cm知识点:等腰三角形的性质章节:图形的性质 / 三角形