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What is the y-value of the solution to the system of equations {3x+4y=4 and 2x−4y=6?

User Ernestine
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1 Answer

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Answer: y = -1/2

Explanation:

Use the elimination method. When setting the equations up, you can see that the y values already cancel out. This makes it easy to find the x value.

3x+4y=4 3x+4y=4

2x-4y=6 -----> (-) 2x-4y=6

For the x value, you would get 2. 5x=10 therefore x=2.

Now that you have your x value, choose one of the original equations(either works). I chose 3x+4y=4. Now, substitute 2 into the x value then solve your equation for the y-value.

3x+4y=4 ---> 3(2)+4y=4

3(2)+4y=4 then becomes 4y=-2 and when you isolate the variable, you get -1/2.

User Artem Vertiy
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