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3х + 4y= 112х-4y = -6

User Gilgad
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1 Answer

2 votes

3x + 4y = 11

2x - 4y = -6

First we isolate x, in the first equation, this way:

3x = 11 - 4y

x = (11 - 4y)/3

Now, we subsitute x in the second equation, this way:

2 (11 - 4y/3) - 4y = -6

22 - 8y/3 - 4y = - 6

22 - 8y - 12y = - 18

Like terms:

-20y = -18 - 22

-20y = -40

y = -40/-20

y = 2

Now, we replace y in the first equation for solving for x, this way:

3x + 4 * 2 = 11

3x + 8 = 11

3x = 11 - 8

3x = 3

x = 3/3

x = 1

The correct answer is x = 1 a

User Waqasahmed
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