SOLUTION: The sum of a number and -7 is -12. solve and check

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Question 117911: The sum of a number and -7 is -12.
solve and check
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

The sum of a number x and -7 is -12 we can write like this:
x%2B%28-7%29+=+-12
x+-+7+=+-+12.....add 7 to the both sides
x+-+7+%2B+7+=+-+12+%2B+7
x+=+-+5
check:
x%2B%28-7%29+=+-12....substitute x
%28-5%29%2B%28-7%29+=+-12
-%285%2B7%29+=+-12
-12+=+-12