let m, n, m1, n1, k be Integer; :: thesis: ( m <> 0 & n <> 0 & (m * m1) + (n * n1) = k implies for x, y being Integer st (m * x) + (n * y) = k holds
ex t being Integer st
( x = m1 + (t * (n / (m gcd n))) & y = n1 - (t * (m / (m gcd n))) ) )
assume A1:
( m <> 0 & n <> 0 & (m * m1) + (n * n1) = k )
; :: thesis: for x, y being Integer st (m * x) + (n * y) = k holds
ex t being Integer st
( x = m1 + (t * (n / (m gcd n))) & y = n1 - (t * (m / (m gcd n))) )
let x, y be Integer; :: thesis: ( (m * x) + (n * y) = k implies ex t being Integer st
( x = m1 + (t * (n / (m gcd n))) & y = n1 - (t * (m / (m gcd n))) ) )
assume A2:
(m * x) + (n * y) = k
; :: thesis: ex t being Integer st
( x = m1 + (t * (n / (m gcd n))) & y = n1 - (t * (m / (m gcd n))) )
A3:
m gcd n <> 0
by A1, INT_2:35;
consider m2, n2 being Integer such that
A4:
( m = (m gcd n) * m2 & n = (m gcd n) * n2 & m2,n2 are_relative_prime )
by A1, INT_2:38;
A5:
( m2 = m / (m gcd n) & n2 = n / (m gcd n) )
by A3, A4, XCMPLX_1:90;
A6:
n2 gcd m2 = 1
by A4, INT_2:def 4;
A7:
( m2 <> 0 & n2 <> 0 )
by A1, A4;
m * (x - m1) = n * (n1 - y)
by A1, A2;
then A8: m2 * (x - m1) =
(n * (n1 - y)) / (m gcd n)
by A5, XCMPLX_1:75
.=
n2 * (n1 - y)
by A5, XCMPLX_1:75
;
then A9:
(x - m1) / n2 = (n1 - y) / m2
by A7, XCMPLX_1:95;
n2 divides m2 * (x - m1)
by A8, INT_1:def 9;
then
n2 divides x - m1
by A6, Th36;
then consider t being Integer such that
A10:
n2 * t = x - m1
by INT_1:def 9;
t = (x - m1) / n2
by A7, A10, XCMPLX_1:90;
then
t * m2 = n1 - y
by A7, A9, XCMPLX_1:88;
then A11:
y = n1 - (t * m2)
;
x = m1 + (t * n2)
by A10;
hence
ex t being Integer st
( x = m1 + (t * (n / (m gcd n))) & y = n1 - (t * (m / (m gcd n))) )
by A5, A11; :: thesis: verum