Question

Solve the system algebraically.

2x + y - 10 = 0
x - y - 5 = 0

What is the value of y?


-5/3
0
5

Answer 1

i am having trouble with this

Answer 2

First, make sure it is set up properly. You want to move the -10 and the 10 to the other side.
2x + y=10
x - y = 5
You want to eliminate the x.
To do that, multiply the bottom equation by -2.
You should get,
(-2x+2y=-10)
Now, you cancel out the x's, add the y's and the solutions.
2x+y=10
-2x+y=-10
You should end up with,
3y=0
Now divide by 3 to get the answer.

Answer 3

thnx

Answer 4

No problem :)