SOLUTION: i really dont understand this lesson well. so my teacher gave me this problem to do on my own and i was wondering was this right:2x-3y=12,x-y=-5 -3y=-2x-12

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: i really dont understand this lesson well. so my teacher gave me this problem to do on my own and i was wondering was this right:2x-3y=12,x-y=-5 -3y=-2x-12       Log On


   

Question 313471: i really dont understand this lesson well. so my teacher gave me this problem to do on my own and i was wondering was this right:2x-3y=12,x-y=-5

-3y=-2x-12 -y=-x+5
y=2/3x+4 y=x+5
Answer by OmniMaestra(21) About Me  (Show Source):
You can put this solution on YOUR website!
So far you are doing great but you aren't finished yet. Now that you've solved both equations for y you can use the transitive property that says
if a=y and y=b then a=b so...
if %282%2F3%29x%2B4=y and y=x%2B5 then
%282%2F3%29x%2B4=x%2B5
Solve for x
subtract 4 from both sides:------->%282%2F3%29x=x%2B5-4
subtract x from both sides------>%282%2F3%29x-x=1
simplify------------------------->-%281%2F3%29x=1
Multiply both sides by -3--------->x=-3
now substitute the -3 into one of the original equations
-y=-x+5
-y=-(-3)+5
-y=8
y=-8