-[(-0.5)+(-51/2)]-16
=-[(-1/2)+(-51/2)]-16
=-（-52/2）-16
=26-16
=10
2,-8
3,-9
12,-38
-2,-3
0,-3
发现和为负数的两个数特征：两数一正一负,负数绝对值大；两数同为负数；两数一负数一零.
-[(-0.5)+(-51/2)]-16等于多少
-[(-0.5)+(-51/2)]-16
=-[(-1/2)+(-51/2)]-16
=-（-52/2）-16
=26-16
=10
2,-8
3,-9
12,-38
-2,-3
0,-3
发现和为负数的两个数特征：两数一正一负,负数绝对值大；两数同为负数；两数一负数一零.