Answer:
"a number" = 7
Step-by-step explanation:
let "a number" = x.
x + 5 = 12
Isolate the variable x. Note the equal sign, what you do to one side, you do to the other. Subtract 5 from both sides.
x + 5 (-5) = 12 (-5)
x = 12 - 5
x = 7
7 is your answer.
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