86×8584-84×8586简便计算
问题描述:
86×8584-84×8586简便计算
RT
要求用地等式,简便计算
答
86*8584-84*8586
=(84+2)*8584-84*(8584+2)
=84*8584+2*8584-84*8584-84*2
=2*(8500+84)-2*84
=2*8500
=17000