45乘45简便方法计算

2024-12-31 22:51:38
推荐回答(2个)
回答1:

(45+5)(45-5)+25=50X40+25=2025.通用做法:Y5XY5=(Y+5)(Y-5)+25

回答2:

45X45
=(50-5)X(50-5)
=50X50-50X5-5X50+5X5
=2500-250-250+25
=2025