Question

si m+n/m-n = 5/2 ; 6m - 4n = 90

Answer 1

m+n/m-n = 5/2
2m+2n=5m-5n
2n+5n=5m+2m
7n=7m
n=m
Luego:
6m - 4n = 90
6m-4m=90
2m=90
m=45
n=45
Ambos tienen igual valor