Difference between revisions of "1955 AHSME Problems/Problem 4"

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<math>\textbf{(A)}\ \text{no real values of }x\qquad\textbf{(B)}\ \text{either }x=1\text{ or }x=2\qquad\textbf{(C)}\ \text{only }x=1\\ \textbf{(D)}\ \text{only }x=2\qquad\textbf{(E)}\ \text{only }x=0</math>
 
<math>\textbf{(A)}\ \text{no real values of }x\qquad\textbf{(B)}\ \text{either }x=1\text{ or }x=2\qquad\textbf{(C)}\ \text{only }x=1\\ \textbf{(D)}\ \text{only }x=2\qquad\textbf{(E)}\ \text{only }x=0</math>
  
==Solution==
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==Solution 1==
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From the equality, <math>\frac{1}{x-1}=\frac{2}{x-2}</math>, we get  <math>{(x-1)}\times2={(x-2)}\times1</math>.
  
From the equality, <math>\frac{1}{x-1}=\frac{2}{x-2}</math>, we get  <math>{(x-1)}*2={(x-2)}*1</math>.
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Solving this, we get, <math>{2x-2}={x-2}</math>.
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Thus, the answer is <math>\fbox{{\bf(E)} \text{only} x = 0}</math>.
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Solution by awesomechoco
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==Solution 2 (answer choices)==
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Looking at the answer choices, we can see B, C, and D are incorrect because <math>x = 1</math> and <math>x = 2</math> result in division by <math>0</math>.
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Plugging in <math>0</math> gives:
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<math>\frac{1}{0 - 1} = \frac{1}{-1} = -1</math>
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<math>\frac{2}{0 - 2} = \frac{2}{-2} = -1</math>
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These two are equal, so the answer is <math>\fbox{{\bf(E)} \text{only} x = 0}</math>.
  
Solving this, we get, <math>{2x-2}={x-2}</math>.
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~anabel.disher
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== See Also ==
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{{AHSME box|year=1955|num-b=3|num-a=5}}
  
Thus, ${x} can only equal 0
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{{MAA Notice}}

Latest revision as of 16:18, 18 June 2025

Problem

The equality $\frac{1}{x-1}=\frac{2}{x-2}$ is satisfied by:

$\textbf{(A)}\ \text{no real values of }x\qquad\textbf{(B)}\ \text{either }x=1\text{ or }x=2\qquad\textbf{(C)}\ \text{only }x=1\\ \textbf{(D)}\ \text{only }x=2\qquad\textbf{(E)}\ \text{only }x=0$

Solution 1

From the equality, $\frac{1}{x-1}=\frac{2}{x-2}$, we get ${(x-1)}\times2={(x-2)}\times1$.

Solving this, we get, ${2x-2}={x-2}$.

Thus, the answer is $\fbox{{\bf(E)} \text{only} x = 0}$.

Solution by awesomechoco

Solution 2 (answer choices)

Looking at the answer choices, we can see B, C, and D are incorrect because $x = 1$ and $x = 2$ result in division by $0$.

Plugging in $0$ gives:

$\frac{1}{0 - 1} = \frac{1}{-1} = -1$

$\frac{2}{0 - 2} = \frac{2}{-2} = -1$

These two are equal, so the answer is $\fbox{{\bf(E)} \text{only} x = 0}$.

~anabel.disher

See Also

1955 AHSME (ProblemsAnswer KeyResources)
Preceded by
Problem 3
Followed by
Problem 5
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
All AHSME Problems and Solutions


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