2n−m2n+m=16
2(n+m)−(n−m)=16
2n+m−n+m=16
22m=24
2m=4
m=2
(am−2n+2p)−1(a2m+n−p)2
Dividing by something raised to −1 is the same as multiplying by it, so:
=(a2m+n−p)2⋅(am−2n+2p)
=a2(2m+n−p)⋅a(m−2n+2p)
=a4m+2n−2p⋅am−2n+2p
=a(4m+2n−2p)+(m−2n+2p)
=a5m
All the n and p terms cancel out.
Substituting m=2 and a=21/10:
a5m=a5×2=a10
=(21/10)10
=210/10
=2