a^(m+1)*b^(m+2)*a^(2n-1)*b=a^5*b^4
a^(m+1+2n-1)*b^(m+2+1)=a^5*b^4
a^(m+2n)*b^(m+3)=a^5*b^4
m+3=4
m=1
m+2n=5
1+2n=5
2n=4
n=2
m+n=1+2=3
a^(m+1)*b^(m+2)*a^(2n-1)*b=a^5*b^4
a^(m+1+2n-1)*b^(m+2+1)=a^5*b^4
a^(m+2n)*b^(m+3)=a^5*b^4
m+3=4
m=1
m+2n=5
1+2n=5
2n=4
n=2
m+n=1+2=3