Respuesta :

a=(1/2(b+c))(h)
1/2bh+1/2ch=a
1/2bh+1/2ch+−1/2bh=a+−1/2bh
1/2ch=−1/2bh+a
1/2chh/2=−1/2bh+ah/2

c=−bh+2a / h