Restrictions
- Thread starter BeccaP
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pka
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As written that statement makes no sense.
Please explain what it means.
HallsofIvy
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As written there are no restrictions. You can multiply any number by 3, you can add any number 5 to any number, and, again, multiply any number by 3. Surely you knew that!
Sorry, it is the denominator of the answer found after simplifying the whole equation.
INSTRUCTIONS: Simplify and state the restrictions on the variable.
2x 8
----------- - ----------- <----Division line
9x^2 + 15x 3x + 5
2x 8
----------- - ------------
3x(3x + 5) 3x + 5
2 8
------------ - ------------
3(3x + 5) 3x + 5
2 8 * 3
------------ - ----------
3(3x + 5) 3(3x + 5)
2 24
----------- - ------------
3(3x + 5) 3(3x+5)
2-24
-----------
3(3x + 5)
-22
----------
3(3x + 5)
22
- -----------
3(3x + 5)
I apologize for the improper division line, I don't know how to make it solid.
Thanks.
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I don't know why I can't get it to stay the way I type it, I keep previewing and editing but it doesn't help.
the 8 goes over the second division line, and the second (3x + 5) goes under it. It just keeps pushing it all to the left
I hope you can decipher it :S
mmm4444bot
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We can text rational expressions using a forward slash and grouping symbols:
EG: 3/(3x + 5)
The slash tells us we have a ratio.
The number before the slash is the numerator.
The grouping symbols after the slash contain the denominator.
As you cannot have zero in any denominator, the expression 3x + 5 must not evaluate to zero.
What value of x causes the expression 3x + 5 to equal zero? That value is your restriction on x.
EG: 3/(3x + 5)
The slash tells us we have a ratio.
The number before the slash is the numerator.
The grouping symbols after the slash contain the denominator.
As you cannot have zero in any denominator, the expression 3x + 5 must not evaluate to zero.
What value of x causes the expression 3x + 5 to equal zero? That value is your restriction on x.
Last edited:
mmm4444bot
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PS: If you would like to "draw" algebraic ratios on these boards, then you must use the CODE tags. Check our FAQ for more information on BBC coding. Cheers ~ Mark :cool:
mmm4444bot
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Ah -- I see that I misread your second post.
So here is another example (using your latest expression) of texting algebraic ratios with grouping symbols.
-22/[3(3x + 5)]
So here is another example (using your latest expression) of texting algebraic ratios with grouping symbols.
-22/[3(3x + 5)]
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The denominator is 3(3x + 5). The numerator is -22.
thus:
22
- _________
3(3x+5)
Can I just ignore the outside 3?
MY original findings for the restriction on x was
3x + 5 = 0
3x = -5
x (can not equal) -5/3
Last edited:
HallsofIvy
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If the denominator is 3(3x+5) (it would have helped if you had told us that to begin with!) then the restriction is that we cannot divide by 0! 3 is never 0 itself so the denominator will be 0 only when 3x+ 5= 0. That is the same as 3x= -5 and then x= -5/3. The fraction you give exists for all x except x= -5/3.
Okay, that makes sense.
That was the restriction I had found originally but then I wanted to be sure...and of course I ended up making things very difficult for everyone trying to help! Sorry! I never thought to add that it was the denominator in the original posting, math isn't my best subject.
mmm4444bot
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You are still trying to "draw" fractions.
I tried to tell you that "drawing" does not work on these boards.
I feel badly that my previous post did not explain this situation adequately.
Maybe you'll understand Karl better. Click here to learn how to text basic mathematical expressions.
Cheers :cool: