MathDB

In rectangular coordinate system, define that if and only if both

x

-axis and

y

-axis of a point are rational numbers, we call it rational point. If

a

is an irrational number, then in all lines that passes

(a,0)

\text{(A)}

There are infinitely many lines, on which there are at least two rational points.

\text{(B)}

There are exactly

n(n\geq2)

lines, on which there are at least two rational points.

\text{(C)}

There are exactly 1 line, on which there are at least two rational points.

\text{(D)}

Every line passes at least one rational point.

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