Question

ayuda porfavor metodo de sustitucion x+y=19 x-1=y/2

Answer 1

x+y=19
x-1=y/2
2(x-1)=y
2x-2=y
2x-y=2
resolvamos

x+y=19
2x-y=2
----------
3x=21
x=7
reemplazando
x+y=19
7+y=19
y=19-7
y=12