Answer:
12−(−5) = 17
Explanation:
The given expression is

We need to find the value of given expression using a number line.
Two numbers are 12 and -5.
Plot these two numbers on the number line.
Now, start form -5 and jump up to 12 on the number line and count the jumps, then the number of jumps is the answer.
From below figure it is clear that the number of jumps between -5 and 12 is 17.
Therefore, the value of given expression is 17.