SOLUTION: I honestly have no idea how to do any of this and my teacher just gave it to us but the problem is y=x-4 y=-x and im not even sure of what the title of these problems are???

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Question 1009586: I honestly have no idea how to do any of this and my teacher just gave it to us but the problem is y=x-4 y=-x and im not even sure of what the title of these problems are???
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
This is a system of equations
y = x-4
y = -x


The first equation given to you is y+=+x-4. Replace the y with -x. Why are we able to do this? Because the second equation says y+=+-x.

So we go from y+=+x-4 to -x+=+x-4

Now we isolate x

-x+=+x-4

-x-x+=+x-4-x Subtract x from both sides

-2x+=+-4

%28-2x%29%2F%28-2%29+=+-4%2F%28-2%29 Divide both sides by -2

x+=+2

Now we use x = 2 to find y

y+=+-x

y+=+-2 Replace x with 2


So x = 2 and y = -2. They pair up to form the ordered pair or point (2,-2)

If you were to graph the two equations y = x-4 and y = -x, you'd find that they cross at the point (2,-2)