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Solve the system of xxuations using elimination: -2x+2y=6 and 7x+4y=34

User Nedec
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Final answer:

To solve the system of equations using elimination, we first matched the y coefficients and subtracted one equation from the other to find x = 2. Substituting x back into one of the original equations gave us y = 5. Checking these values in both original equations confirms the solution is correct.

Step-by-step explanation:

To solve the system of equations using elimination, we want to find a way to eliminate one of the variables by combining the two equations. We have the equations -2x + 2y = 6 and 7x + 4y = 34.

First, let's try to eliminate the variable y. To do this, we can multiply the first equation by 2 so that the coefficients in front of y in both equations match. Multiplying the first equation by 2 gives us:

-4x + 4y = 12

Now we have:

  • Equation 1: -4x + 4y = 12
  • Equation 2: 7x + 4y = 34

Next, we subtract Equation 1 from Equation 2 to eliminate y:

(7x + 4y) - (-4x + 4y) = 34 - 12

This simplifies to:

11x = 22

Divide both sides by 11:

x = 2

Now that we have the value for x, we can substitute it back into one of the original equations to solve for y. Using the first equation -2x + 2y = 6:

-2(2) + 2y = 6

-4 + 2y = 6

Add 4 to both sides:

2y = 10

Divide both sides by 2:

y = 5

Therefore, the solution to the system of equations is x = 2 and y = 5. It is always a good idea to check the solution by plugging the values back into the original equations to ensure they satisfy both.

User Seth Flowers
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