# I Diophantine equation

#### Ling Min Hao

The given question required me to solve 7x+4y =100 by using diophantine equation . I get an answer for x = 100 - 4t and y = 200 - 7t . But his given answer is x = 4t and y = 25-7t . I think both of mine and the answer given is correct but I can't figure out how he get another solution

#### jedishrfu

Mentor
What values can t have?

#### mathman

The given question required me to solve 7x+4y =100 by using diophantine equation . I get an answer for x = 100 - 4t and y = 200 - 7t . But his given answer is x = 4t and y = 25-7t . I think both of mine and the answer given is correct but I can't figure out how he get another solution

#### mfb

Mentor
I think you mean -7x+4y=100.

#### mathman

I think you mean -7x+4y=100.
You are right - my typo.

#### Ling Min Hao

Both answer is correct since both can be used to find the value of x and y , it's just I don't understand how he get the answer using dio phantine method

#### mathman

Both answer is correct since both can be used to find the value of x and y , it's just I don't understand how he get the answer using dio phantine method
I am not familiar with the Diophantine method. However, by substituting your answer into the original equation, it is obviously wrong. His answer is obviously correct. I can only guess you are misusing the Diophantine method.

"Diophantine equation"

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