Question

x-3<-12

Answer 1

treat it like an equality and solve for x

Answer 2

the steps involved in solving this

x-3=-12

as exactly the same as the steps in solving this:
x-3<-12



***rule doesn't apply to your question but still good to know****
The only time you need to worry is when you divide or multiply both sides by a negative, when you do that you simply flip the inequality symbol,

by flip I mean if you multiplied both sides by -1, the inequality would go

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