SOLUTION: Find the point of intersection of the lines: 2x+y=3 x-4y=6 I tried doing elimination to solve this and it said it was wrong (I'll put my work below) 2x+y=3 -2(x-4y=-12) -

Algebra ->  Linear-equations -> SOLUTION: Find the point of intersection of the lines: 2x+y=3 x-4y=6 I tried doing elimination to solve this and it said it was wrong (I'll put my work below) 2x+y=3 -2(x-4y=-12) -      Log On


   

Question 1200483: Find the point of intersection of the lines:
2x+y=3
x-4y=6
I tried doing elimination to solve this and it said it was wrong (I'll put my work below)
2x+y=3
-2(x-4y=-12)
------------
9y=-9
y=-1
------
2x+y=3
2x-1=3
2x=4
x=2
------
So that would mean y is -1 and x is 2? (2,-1)
Answer by josgarithmetic(39838) About Me  (Show Source):
You can put this solution on YOUR website!
--------------------------------------------------
Find the point of intersection of the lines:
2x+y=3
x-4y=6
-------------------------------------------------

2%286%2B4y%29%2By=3-------using substitution

12%2B8y%2By=3
9y%2B12=3
9y=-9
highlight%28y=-1%29

Now solve for x.
x=4y%2B6
x=4%28-1%29%2B6
highlight%28x=2%29

Intersection Point, (2,-1)


---------NOTE-----------
---------------------------

You can choose from Elimination or Substitution or by graphing method, depending on your choice or the exercise's requirements. I chose substitution. You could choose a different method if you want.


------
------

If use Elimination, a possible way:
2x%2By=3
x-4y=6

4%282x%2By%29=4%283%29
x-4y=6

8x%2B4y=12
x-4y=6
ADD.
9x%2B0=18
highlight%28x=2%29

Returning to original equations:
2x%2By=3
2%28x-4y%29=2%2A6

2x%2By=3
2x-8y=12

SUBTRACT.
-9y=9
highlight%28y=-1%29