Question

Using a sheet of graph paper, solve the following system of equations graphically. Be sure to show any work, use a straight edge, and be neat. When you are finished, enter the solution set in the box below and turn in your graph paper to your teacher. x + y = 0 x - y + 2 = 0

Answer 1

(-1,1)

Explanation:

Given system is

`\left \{ {{x+y=0} \atop {x-y+2=0}} \right.`

If we graph, the solution would be the interception point between these two lines, because each linear equation represents a line. The lines are attached.

In the graph, you can observe that the solution is the point (-1,1), that is x = -1 and y = 1.

Now, if we want to solve this system by another method, we can just sum both equations and solve for x

`\left \{ {{x+y=0} \atop {x-y+2=0}} \right.`

`2x+2=0\\x=(-2)/(2)=-1`

Then, we replace this value in one equation to find the other value

`x+y=0\\-1+y=0\\y=1`

Therefore, the solution is (-1,1)