解方程：n(21+19+2n)/2+(9-n)(32+16+2n)/2=241过程要清楚
问题描述：
解方程：n(21+19+2n)/2+(9-n)(32+16+2n)/2=241过程要清楚
答
n(21+19+2n)/2+(9-n)(32+16+2n)/2=241n(40+2n)/2+(9-n)(48+2n)/2=241n(20+n)+(9-n)(24+n)=24120n+n^2+9(24+n)-n(24+n)=24120n+n^2+216+9n-24n-n^2=2415n+216=2415n=25n=5