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July 9th, 2008, 04:53 PM   #1
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NEED Help Quick

i need quick help to solve these problem i keep running into problems when i check my answer

Square root of 3x+1 = 3+ square root of x-4

and

absolute value of 2x+1 = x-1
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July 9th, 2008, 10:15 PM   #2
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Re: NEED Help Quick

Hi



which we rearrange to


then square both sides:


Then we have


so:
(x-5)=0." />

The two solutions are and (which we can check are both consistent with )



Secondly,



can be examined in two separate cases: and

If then so This has one solution at but this is not valid since we are looking only at

On the other hand, if then so This has one solution at but again this is not valid since we are looking only at

So has no solutions.
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July 10th, 2008, 09:15 PM   #3
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Re: NEED Help Quick

[color=#4000BF]Dear Helpless:

|2x + 1| = x - 1 is readily solved if you consider the graphs of y1 = |2x + 1| and y2 = x - 1. y2 has x-intercept at (1, 0), with slope = 1. y1 has x-int. at (-1/2, 0). Clearly, were there solutions, y2 would intersect the "right-most" branch of y1 in the first quadrant. Given the aforesaid, however, a moment's reflection indicates that no such intersection exists, i.e., the equation is without solutions.

Regards,

Rich B.[/color]
rmath4u22aol.com
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