How do you simplify #13 - 5 + 1 # using PEMDAS?

1 Answer
Mar 31, 2018

Answer:

#9#

Explanation:

The problem arises in identifying the adds and the subtracts!

The question does NOT mean #13-(5+1)#, where the addition is seen as #5+1#

Remember that a sign belongs to the number on the right.

What we actually have is

#(+13) +(-5) +(+1)#

I prefer to have students rearranging the terms first, with the ADDS at the beginning and the SUBTRACTS at the end.

#13+1-5 = 9#

Or just work from left to right.

#color(blue)(13-5)+1#

#=color(blue)(8)+1#

#=9#