need help here please (1 Viewer)

Mark576

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Solve 4x < / 15 < / -9x

only confused because the answers say that x = 0 is included, when clearly it doesn't satisfy the inequation.

btw, < / means less than or equal to. thanks!
 
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Mark576

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Yeah it didn't show up at first, I had to change the symbols used.
 

PC

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You are coming up with the strangest questions!

Do it in bits.

1. 4x <= 15
x <= 3 3/4

2. 15 <= –9x
–9x => 15 (just swap the sides around)
x <= –1 2/3 (remember to change the direction of the inequation when dividing by a negative)

Now both these conditions have to hold simultaneously. So the overall solution must be x <= -1 2/3.

x=0 is not a valid solution, as it doesn't satisfy the right part of the equation.
 

Mark576

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yeah thanks, I thought that was it - incorrect answers are always so confusing! haha
 

Mark576

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They're just questions from my first preliminary mathematics exam
 

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