Respuesta :

perixwinkle
33
The lines stand for absolute value. The expression would then look like:
13+26-18+12
39-18+12
21+12
33


CoffeeHead
Ah, let me help you on this one.

These weird lines (|) are actually indicators of absolute value.

All of the negative numbers will be transformed into non-negative ones.

Neat, huh?

13+26-18+12 equals to 33



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