6m+5n= 1...............................②
5n=3m-8 from ( 1)
Substitute (2)
Get 6m+3m-8= 1.
That is 9m=9.
Solution m= 1
Substitute m= 1 into ②.
That is 6* 1+5n= 1.
Solution n=- 1
That is, m= 1 and n=- 1.