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Solve the system of linear equations by elimination.

−x+y=4
x+3y=4

please explain

User Kader
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2 Answers

6 votes
Y=1. Let me know if you need more of an explanation.
User Takien
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Answer: y = 2 x = -2

Explanation:

-x + y = 4

x + 3y = 4

Since x and -x are opposite, we can use the system of elimination

To do that, we add the first equation and the second equation together

-x + y = 4

+

x + 3y = 4

4y = 8

Now we solve for y

4y = 8

Divide both sides by 4

y = 2

Since we now know y, we can solve for x by substituting y for 2 in one of the equations.

x + 3y = 4

Substitute y for 2

x + 3 (2) = 4

x + 6 = 4

Subtract 6 from both sides

x = -2

Hope I helped! And sorry if I repeated somethings.

User Mattpr
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