can someone please explain why the answer is E Is it b/c y is indeterminable when r = 5? is "indeterminable" an ambiguous answer?
(y+3)(y-1) - (y-2)(y-1) = r(y-1), what is the value of y?
(1) r^2 = 25
(2) r = 5
thanks
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equations / squares problem
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topspin360
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Yes,topspin360 wrote:can someone please explain why the answer is E Is it b/c y is indeterminable when r = 5? is "indeterminable" an ambiguous answer?
(y+3)(y-1) - (y-2)(y-1) = r(y-1), what is the value of y?
(1) r^2 = 25
(2) r = 5
thanks
factoring out (y-1) will give y+3-y+2=r and further r=5 only when (y-1)=!0 (not equal to 0)
in case of y-1=0 and y=1 we may have r=any real value
st(1) r^2=25 implies r=|5| Insuff
st(2) r=5 Insuff
combined also Insuff
answer is e)
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(y+3)(y-1) - (y-2)(y-1) = r(y-1)topspin360 wrote:can someone please explain why the answer is E Is it b/c y is indeterminable when r = 5? is "indeterminable" an ambiguous answer?
(y+3)(y-1) - (y-2)(y-1) = r(y-1), what is the value of y?
(1) r^2 = 25
(2) r = 5
thanks
(y-1)( (y+3) - (y-2) ) = r(y-1)
(y-1)(5) = r(y-1)
5(y-1) - r(y-1) = 0
(5-r)(y-1) = 0.
r=5 is the only value that satisfies both statements.
If r=5, y can be any value.
INSUFFICIENT.
The correct answer is E.
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I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
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