5.3x3.5+7.5x5.3-5.3
=5.3x3.5+5.3x7.5-5.3x1
=5.3x(3.5+7.5-1)
=5.3x10
=53
【很高兴为你解决以上问题,希望对你的学习有所帮助!】≤、≥ ∠