Question

Use addition to solve the linear system of equations.
x-y=4
x+2y=4

Answer 1

Hey, There 20percntcooler! :)

To solve these equations, we will need to substitute.

`x-y=4`
or

`4+y=x`

We can substitute this for x so, we don't have to deal with two different variables.

`x+2y=4`
or if substituted:

`4+y+2y=4`

Solve for y.

`4+y+2y=4`
Add like terms.

`4+3y=4`
Subtract 4 from both sides.

`(4+3y)-4=(4)-4`

`3y=0`
Divide both sides by 3.

`(3y)/3=(0)/3`

`y=0`

Now lets input the value for y into the equation to find the value of x.

`x-0=4`
Add 0 to both sides.

`(x-0)+0=(4)+0`

`x=4`


`x=4`

`y=0`

Hope this helps.
-Benjamin