SOLUTION: Where on the graph of 3x-y = 12 are the x and y coordinates opposites of each other? I started out by y = mx + b and changed the equation to y = 3x - 12 but i am stuck from there

Algebra ->  Graphs -> SOLUTION: Where on the graph of 3x-y = 12 are the x and y coordinates opposites of each other? I started out by y = mx + b and changed the equation to y = 3x - 12 but i am stuck from there       Log On


   



Question 37228: Where on the graph of 3x-y = 12 are the x and y coordinates opposites of each other?
I started out by y = mx + b and changed the equation to y = 3x - 12 but i am stuck from there

Answer by jcmtnez(53) About Me  (Show Source):
You can put this solution on YOUR website!
If you want a point in which the x is opposite to y the point is (x,-x),
To find such point we have to solve the equation for y=-x
3x-y = 12,
y=3x-12,
(-3)=3x-12,
-3+12=3x,
then 9=3x,
finally we get x=3
Therefore the point is (3,-3), In wich the x and the y are opposites.