If the absolute value of a is equal to a, then a must be positive

If the absolute value of a is equal to a, then a must be positive

Pro, not necessarily
0 is a special example. The absolute value of 0 is still 0, but it is neither positive nor negative

The absolute value of the difference between X and 2 plus 1 equals 2

|x-2|+1=2

It is known that a is the sum of the opposite number of 7 and 12, and B is 14 less than the absolute value of - 10

A is the opposite of 7 and the sum of 12
A=5
B is 14 less than the absolute value of - 10
B=-4

If a and B are opposite to each other, C and D are reciprocal to each other, and the absolute value of M is 2, find the absolute value of a + B / 7-CD + 2 times M

a+b=0
cd=1
m=±2
So when m = 2, the original formula = - 1 + 2 * 2 = 3
When m = - 2, the original formula = - 1 * 2 * - 2 = - 5
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