SOLUTION: Solve by elimination 5x-y=13 x+2y=1

Algebra ->  College  -> Linear Algebra -> SOLUTION: Solve by elimination 5x-y=13 x+2y=1       Log On


   

Question 298800: Solve by elimination
5x-y=13
x+2y=1
Found 3 solutions by user_dude2008, nerdybill, profemmanuel2q:
Answer by user_dude2008(1862) About Me  (Show Source):
You can put this solution on YOUR website!
5x-y=13
x+2y=1

10x-2y=26
x+2y=1

11x+0y=27
11x=27
x=27/11

10x-2y=26
10(27/11)-2y=26
270-22y=286
-22y=16
y=-16/22
y=-8/11

Answers: x=27/11, y=-8/11

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
Starting with:
5x-y=13
x+2y=1
.
Multiply both sides of the top equation by 2:
10x-2y=26
x+2y=1
.
Add the two equations together:
10x-2y=26
x+2y=1
-----------
11x =27
x = 27/11
.
Plug the above into:
x+2y=1
27/11+2y=1
Solve for y:
27+22y=11
22y = -16
y = -16/22
y = -8/11
.
Solution:
x = 27/11
y = -8/11




Answer by profemmanuel2q(4) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by elimination
5x-y=13 ---- 1
x+2y=1 ---- 2
You need to decide the variable you want to eliminate. i will eliminate the variable y
Multiple Equation 1 by 2
10x - 2y = 26 - -- 1
x + 2y = 1 ---- 2
Eqn. 1 + Eqn 2
11x = 27
11x/11 = 27/11
Therefore, x = 27/11
Put x = 27/11 into Eqn. 1
5x-y=13
5(27/11) - y = 13
y = 137/11 - 13
y = (137 - 143)/11
y= -6/11