Question

解方程：n(21+19+2n)/2+(9-n)(32+16+2n)/2=241过程要清楚

Answer 1

n(21+19+2n)/2+(9-n)(32+16+2n)/2=241

n(40+2n)/2+(9-n)(48+2n)/2=241

n(20+n)+(9-n)(24+n)=241

20n+n^2+9(24+n)-n(24+n)=241

20n+n^2+216+9n-24n-n^2=241

5n+216=241

5n=25

n=5