Verified Answer :

nobrains

Well, you can reorder the terms into -15 + 32, that's the commutative property.
You can draw 32 dots or something and draw x's on 15 of them representing the subtraction of 15 dots.

32 - 15 = 17

Now, lets write some sentences on how to write this. 

We could write :-

15 + x = 32
x would still equal 17

x = 17

Now, another way is a word problem

There were 32 students in class, later, 15 left to go talk to the teacher. How many students are left at the class?

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