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1 vote
X + 2y =6
X- y =3
Solution?

User Aldith
by
8.0k points

2 Answers

1 vote
x+2y=-6-----> -1x-2y=-6
x-y=3 -----> x-y=3
-3y/-3=-6/-3
y=2
x+2(2)=-6, multiply, then subract to both sides

(2,2)
User Joe Ruello
by
9.0k points
6 votes
Since one equation has a negative y and the other has a positive y, I'm going to use those since they cancel each other out. Before that, the two y's need to be equal to each other.

x+2y=6
x-y=3

Multiply the bottom equation by two so then you have:

x+2y=6
2x-2y=6

The y's now cancel out:

x=6
2x=6

Add them together

3x=12

Divide

x=4.

To find y, plug x into either equation (*don't have to do both, but I will)

(4)+2y=6
(4)-y=3

Subtract four

2y=2
-y=-1

Divide each

2y/2 = 2/2
y=1

-y/-1 = -1/-1
y=1

The answer is:
x=4
y=1

I hope that helps!
User SQB
by
8.5k points

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