Exercise · ZW-LINEAR-DIOPHANTINE-EQUATION-005 · ★★☆ Intermediate

Does the equation \(4x+6y=5\) have integer solutions?

Choose one option.

Show answer
  • C. No, because \(\gcd(4,6)=2\) does not divide \(5\)

Explanation

The gcd of \(4\) and \(6\) is \(2\), which does not divide \(5\), so there is no solution. Having even coefficients is not enough, and solutions need not be positive.

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Review the concept: Linear Diophantine equation

A linear Diophantine equation is \(ax+by=c\) with integer coefficients, where we seek integer pairs \(x,y\) as solutions.

\[x=x_0+\frac{b}{d}t,\quad y=y_0-\frac{a}{d}t,\quad t\in\mathbb{Z}\]

More practice problems: linear diophantine equation

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