How do you evaluate #−7 − 8 #?

2 Answers
Jun 17, 2018

Answer:

#-15# is the answer.

Explanation:

You are subtracting. So -7-8 gives us #-15#

Jun 17, 2018

Answer:

Most likely: #color(red)(-15)#
Alternate possibility: #color(blue)(+1)#

Explanation:

In general PEDMAS is normally specified as being evaluated from left to right (when operations are at the same level).
Therefore #-7-8#
would be evaluated as #color(red)(((-7)-8)=-15)#

However, I have encountered some computer programming languages/environments that claim to be PEDMAS but which evaluate right to left,
in which case #color(blue)(-7-8=(-(7-8))=(-(-1))=+1)#