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.