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Contests
National and Regional Contests
USA Contests
MAA AMC
AMC 12/AHSME
1978 AMC 12/AHSME
6
6
Part of
1978 AMC 12/AHSME
Problems
(1)
Number of Distinct Pairs
Source: 1978 AHSME Problem 6
5/31/2014
The number of distinct pairs
(
x
,
y
)
(x,y)
(
x
,
y
)
of real numbers satisfying both of the following equations: \begin{align*}x&=x^2+y^2, \\ y&=2xy\end{align*} is
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(
A
)
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0
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(
B
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1
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(
C
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2
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(
D
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3
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(
E
)
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4
<span class='latex-bold'>(A) </span>0\qquad<span class='latex-bold'>(B) </span>1\qquad<span class='latex-bold'>(C) </span>2\qquad<span class='latex-bold'>(D) </span>3\qquad <span class='latex-bold'>(E) </span>4
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(
A
)
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0
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(
B
)
<
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1
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>
(
C
)
<
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2
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(
D
)
<
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3
<
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>
(
E
)
<
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>
4
AMC