计算：根号9/16-根号16/25=____
问题描述：
计算：根号9/16-根号16/25=____
答
=3/4-4/5
=15/20-16/20
=-1/20
计算：根号9/16-根号16/25=____
=3/4-4/5
=15/20-16/20
=-1/20