solve the inequality –x + 3 7...
Why must you flip the inequality symbol when you divide by a negative number?

You know that if the symbol is not flipped you will end up with a false statement, but why is that so?

Question

solve the inequality –x + 3 > 7...
 Why must you flip the inequality symbol when you divide by a negative number?

You know that if the symbol is not flipped you will end up with a false statement, but why is that so?

anonymous · Answer

depends on what your definition of $>$ is 
but we can show by a simple example 
we know $-2<1$ but if you multiply both sides by $-1$ you get 
$2>-1$

anonymous · Answer

X<-4 but i don't know how to explain it sorry...

anonymous · Answer

so if you multiply or divide by a negative number, you have to change the inequality

xochital · Answer

alright, so how do you solve the inequality. could you show steps please? :)

anonymous · Answer

yupp give me a sec

anonymous · Answer

subtract 3
change the sign of both sides and also change the sense of the inequalty

anonymous · Answer

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