/>解方程组：
｛ x+2y =m-3
｛ -3x+2y =m+17
得 x = -5,y = (m+2)/2
因为 y 比 x 大8,即 y = x+8
所以 (m+2)/2 = -5+8
即 m+2 = 6
得 m=4
m²-3m+2
= (m-1)(m-2)
= 3×2
= 6

~ 满意请采纳,不清楚请追问.
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