两个两位数的和除以3,余数是2;差除以3,余数是0,问这两个两位数各是多 ...答:x+y = 3n+2 x-y = 3m 两式相加:2x = 3(n+m) + 2 两式相减:2y = 3(n-m) + 2 显然,n 与 m 皆为偶数。此解不唯一。举例:取 n = 10, m = 2 ==> n-m = 8, y = 13, n+m = 12, x = 19 取 n = 12, m = 2 ==> n-m = 10, y = 16, n+m = ...
两个两位数的和除以3,余数是2;差除以3,余数是0,问这两个两位数各是多 ...答:x+y = 3n+2 x-y = 3m 两式相加:2x = 3(n+m) + 2 两式相减:2y = 3(n-m) + 2 显然,n 与 m 皆为偶数。此解不唯一。举例:取 n = 10, m = 2 ==> n-m = 8, y = 13, n+m = 12, x = 19 取 n = 12, m = 2 ==> n-m = 10, y = 16, n+m = ...