Respuesta :
P=a+b+c
we can rewrite this as a+b+c=P
a+b+c-a=P-a
b+c=P-a
b+c-b=P-a-b
c=P-a-b
we can rewrite this as a+b+c=P
a+b+c-a=P-a
b+c=P-a
b+c-b=P-a-b
c=P-a-b