Respuesta :

Answer:

x=10

y=0

Step-by-step explanation:

In order to use substitution you need to pick an equation and get one of the variables alone. I'm going to use the second equation and get x alone.

x+2y=10      Subtract the 2y on both sides to get x by itself.

 -2y  -2y

x= -2y+10   Now plug this in to the first equation for x.

2(-2y+10)+4y= -20  To start you distribute the 2 to both terms inside the parenthesis.

2(-2y)+2(10)+4y= -20   Simplify.

-4y+20+4y= -20    Next add your like terms together (-4y+4y)

When you do this you should get 0y which just means y=0. Now you can take that and plug it into one of the equations for y. I choose to use the second equation again. x+2(0)=10, therefore x=10