SOLUTION: I am stuck on a problem, my teacher only wants me to use the Elimination method 6x-y=20 3x-y=7 I am getting x=3 but when I substitute for x in the second equation I get 6(3) +

Algebra ->  Linear-equations -> SOLUTION: I am stuck on a problem, my teacher only wants me to use the Elimination method 6x-y=20 3x-y=7 I am getting x=3 but when I substitute for x in the second equation I get 6(3) +      Log On


   

Question 414087: I am stuck on a problem, my teacher only wants me to use the Elimination method
6x-y=20
3x-y=7
I am getting
x=3 but when I substitute for x in the second equation I get
6(3) + y = 20
18 + y = 20
but I can't divide each side by 18 evenly, how do I solve for y?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

solving by Elimination method

6x-y = 20

3x-y = 7



 6x-y = 20

-3x+y = -7   | Multiplying the second Eq by -1 to eliminate y

   3x = 13

    x = 13/3 and y = 6    ( y = 3x -7 from the 2nd origial Eq )

  Solution is (13/3, 6)

CHECKING our Answer***

 6x-y = 20

6*(13/3)- 6 = 26 - 6 = 20