Exercise · ZW-BEZOUT-S-IDENTITY-007 · ★★☆ Intermediate
For \( a=30 \) and \( b=12 \), which pair \( (x,y) \) satisfies \( 30x+12y=6 \)?
Choose one option.
Show answer
- B. \( (1,-2) \)
Explanation
With \( x=1 \) and \( y=-2 \) we get \( 30-24=6 \). The pair \( (1,2) \) gives 54, not 6, so it comes from a sign error.
Review the concept: Bézout's identity
Bézout's identity states that, for integers \( a \) and \( b \) not both zero, there exist integers \( x \) and \( y \) such that \( ax+by=\gcd(a,b) \).
\[ax+by=\gcd(a,b) \text{ for some } x,y\in\mathbb{Z}\]
More practice problems: bézout's identity
- ZW-BEZOUT-S-IDENTITY-001 State Bézout's identity for two integers a and b .
- ZW-BEZOUT-S-IDENTITY-002 What is the smallest positive integer that can be written as 12x+18y with x,y∈ℤ ?
- ZW-BEZOUT-S-IDENTITY-003 Give the greatest common divisor of 35 and 14 to use in Bézout's identity.
- ZW-BEZOUT-S-IDENTITY-004 Does Bézout's identity say that ax+by can equal any integer when a and b are coprime?
- ZW-BEZOUT-S-IDENTITY-005 Which statement about the set \ax+by : x,y∈ℤ\ is correct?
- ZW-BEZOUT-S-IDENTITY-006 If gcd(a,b)=d , which of these equations has an integer solution x,y for every such a and b ?
- ZW-BEZOUT-S-IDENTITY-008 Can 8x+12y equal 2 for some integers x,y ?
- ZW-BEZOUT-S-IDENTITY-009 For a=252 and b=198 , with gcd=18 , which pair (x,y) satisfies 252x+198y=18 ?