Equation; what is x+y=3 x-2y=0?

x = 3 and y = 1

Step-by-step explanation:

Lets name the first equation as equation 1.

[Equation 1] x + y = 3

Then name the second equation as equation 2.

[Equation 2] x - 2y = 0

The first purpose is to eliminate one of the variable. In this case, it looks like it is easier to eliminate x since both equations have single x.

We will use [Equation 1] - [Equation 2] to eliminate x and find the value of y.

(x + y) - (x - 2y) = 3 - 0

x + y - x + 2y = 3

3y = 3

y = 1

Now that we know y = 1, we will substitute this value into any of the two equations to find the value of x. Here, I choose to substitute into [equation 1].

x + y = 3

x + 1 = 3

x = 2

So now we found out that x = 2 and y = 1.