solving using elimination?

Question

3x+y=5
2x+y=10

Answer 1

3x+y=5
-(2x+y=10)
x=-5
3(-5)+y=5
y=20
(-5,20)

Answer 2

since the y's have the same number in front of them (1) multiply one of the equations by -1. I pick the second one;therefore you get

3x + y = 5
-2x - y = -10
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Add each 'column' you get

x = -5

Plug the x back into the first problem
3(-5) + y = 5
-15 + y = 5
y = 20

thus your answer is

(-5,20)