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Solve, using linear combination.

4x + y = 5

3x + y = 3


(0, _3)

(0, 5)

(2, _3)

(_3, 7)

User AlexWei
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1 Answer

7 votes

Multiply the first equation by -1 to get -4x - y = --5

Then add the second equation 3x + y = 3

+ ____________

-x = -2 or x = 2


then plug in 2 for x in one of the equations and solve for y 4(2) + y = 5

8 + y = 5

Subtract 8 from both sides y = -3


So x = 2, y = -3 or (2,-3)

User David Brower
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