2x − 1 < 3x + 2
The cubes in the title are abs value signs
My working out is:The solution is:Why is the x<-3 sign that way around, I thought if you divide by a negative the sign flips?
My working out is:
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(edited 7 years ago)
Original post by TheGreatPumpkin
The cubes in the title are abs value signs
Why is the x<-3 sign that way around, I thought if you divide by a negative the sign flips?
Why is the x<-3 sign that way around, I thought if you divide by a negative the sign flips?
You have to be a bit careful with modulus inequalities, just like solving quadratic inequalities is different to solving quadratic equations.
I would definitely recommend drawing a graph. You have two simple linear graphs so it shouldn't be hard to sketch them and see what's going on.
This video deals with a similar problem and shows you two methods you can use.
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