No Integral Solution for x & y when c Not Divisible by d

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In summary, the conversation discusses the equation ax+by=c and its lack of integral solutions when a, b, and c are integers and d is a non-zero integer that divides a and b but not c. It is suggested to replace a and b with their respective integer division forms and see that there is no integral solution.
  • #1
kathrynag
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Homework Statement


For, a, b, c[tex]\in[/tex]integers and D[tex]\in[/tex]integers -{0}, if a and b are divisible by d, and c is not divisible by d then the equation ax+by=c has no integral solution for x and y.


Homework Equations





The Attempt at a Solution


ax+by=c
a/dx+b/dx=c
1/d[ax+by]=c
ax+by=cd
 
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  • #2
Where did the d in a/d come from? You can't just "stick" it into part of the equation.

Saying "d divides a" means a= dn for some integer n. Saying "d divides b" means b= dm for some integer m. Replace a and b in your equation by that and see what happens.
 
  • #3
HallsofIvy said:
Where did the d in a/d come from? You can't just "stick" it into part of the equation.

Saying "d divides a" means a= dn for some integer n. Saying "d divides b" means b= dm for some integer m. Replace a and b in your equation by that and see what happens.

dnx+dmx=c
d(nx+mx)=c
 
  • #4
I don't know if that was the correct way to do it and then maybe say since we don't have a dpc then there is no integral solution?
 

FAQ: No Integral Solution for x & y when c Not Divisible by d

1. What does it mean when there is no integral solution for x and y when c is not divisible by d?

When there is no integral solution for x and y when c is not divisible by d, it means that there are no whole number values for x and y that satisfy the equation c = dx + dy. In other words, there is no combination of x and y that can be added together to equal c when d does not evenly divide into c.

2. Why is it important to find integral solutions for equations involving c and d?

Finding integral solutions for equations involving c and d is important because it helps us understand the relationships between numbers and how they can be combined to equal a specific value. It also allows us to solve real-world problems and make accurate calculations.

3. What happens if c is divisible by d in an equation involving x and y?

If c is divisible by d in an equation involving x and y, there will be an infinite number of integral solutions for x and y. This is because any multiple of d can be divided evenly by d, so there are an infinite number of combinations of x and y that can be added together to equal c.

4. Can there be non-integer solutions for x and y when c is not divisible by d?

No, there cannot be non-integer solutions for x and y when c is not divisible by d. This is because the definition of an integral solution is a solution in which both x and y are whole numbers. If c is not divisible by d, there are no whole number values that can satisfy the equation c = dx + dy.

5. How can we determine if there are integral solutions for x and y when c is not divisible by d?

We can determine if there are integral solutions for x and y when c is not divisible by d by using the Euclidean algorithm. This algorithm helps us find the greatest common divisor of two numbers, which can then help us determine if there are any integral solutions for x and y. If the greatest common divisor of c and d is not equal to 1, then there are no integral solutions. If the greatest common divisor is 1, then there will be integral solutions for x and y.

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