若n(n不等于0)是关于x的方程5x^2+3mx+2n=0的根,则5m+3n的值等于多少?看清楚!是5m+3n的值!

n t=2n/5,t=2/5
n+t=-3m/5--> m=-5(n+t)/3=-(5n+2)/3
5m+3n=-5(5n+2)/3+3n=-(16n+10)/3
将n代入方程得：5n^2+3mn+2n=0
因n不为0,两边除以n,得：5n+3m+2=0
移项,得：5n+3m=-2
m=-5(n+t)/3=-(5n+2)/3
5m+3n=-5(5n+2)/3+3n=-(16n+10)/3