Question

Slove using linear combination 3x+y =4 2x+y=5

Answer 1

Answer: x = -1, y =7

Explanation:

Answer 2

x = -1, y =7

Explanation:

3x+y =4

2x+y=5

Multiply the second equation by -1 and add to the first

3x+y =4

-2x-y=-5

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x = -1

Now find y

3x+y = 4

3(-1) +y = 4

-3+y = 4

Add 3 to each side

-3+3 +y = 4+3

y =7