Given (m-2) ^ 2 + | 2m-n | = 0, find the value of m ^ 2-MN + 2n ^ 2,

Given (m-2) ^ 2 + | 2m-n | = 0, find the value of m ^ 2-MN + 2n ^ 2,

∵(m-2)²+|2m-n|=0
∴m-2=0,2m-n=0
∴m=2,n=4
∴m²-mn+2n²
=2²-2×4+2×4²
=4-8+32
=28