x/（a+m）+y/（b+m）=1
x/（a+n）+y/（b+n）=1
x/（a+m）+y/（b+m）=1 .x(b+m)+y(a+m)=(b+m)(a+m).x+y(a+m)/(b+m)=(a+m)
x/（a+n）+y/（b+n）=1 .x(b+n)+y(a+n)=(b+n)(a+n).x+y(a+n)/(b+n)=(a+n)
y(a+m)/(b+m)-y(a+n)/(b+n)=(a+m)-(a+n)
y[(a+m)/(b+m)-(a+n)/(b+n)]=(m-n)
y[(a+m)(b+n)-(a+n)(b+m)]/[(b+n)(b+m)]=(m-n)
y[(ab+bm+an+mn)-(ab+bn+am+mn)]/[(b+n)(b+m)]=(m-n)
y[bm+an-bn-am]/[(b+n)(b+m)]=(m-n)
y[(bm-am)+(an-bn)]/[(b+n)(b+m)]=(m-n)
y[m(b-a)+n(a-b)]/[(b+n)(b+m)]=(m-n)
y[(b-a)(m-n)]/[(b+n)(b+m)]=(m-n)
y(b-a)=[(b+n)(b+m)]
y=[(b+n)(b+m)]/(b-a)
x/（a+m）+y/（b+m）=1
x/（a+m）+{[(b+n)(b+m)]/(b-a)}/（b+m）=1
x/（a+m）+[(b+n)(b+m)]/[(b-a)(b+m)]=1
x/（a+m）=1 -[(b+n)(b+m)]/[(b-a)(b+m)]
x/（a+m）={[(b-a)(b+m)] -[(b+n)(b+m)]}/[(b-a)(b+m)]
x/（a+m）={(b+m)(b-a -b-n)}/[(b-a)(b+m)]
x/（a+m）=(-a -n)/(b-a)
x/（a+m）=(a+n)/(a-b)
x= [(a+m)(a+n)]/(a-b)
x= [(a+m)(a+n)]/(a-b)
y=[(b+n)(b+m)]/(b-a)