Question

a+18=-12

Answer 1

Solve for a:
a+18 = -12
Isolate terms with a to the left hand side.
Subtract 18 from both sides:
a+(18-18) = -12-18
Look for two terms that sum to zero.
18-18 = 0:
a = -12-18
Evaluate -12-18.
-12-18 = -30:

Answer 2

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