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Solve the system of equations using elimination method: 7x - 6y = -6 and -9x + 6y = 18.

User Mjr
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Final answer:

To solve the given system of equations using elimination, add them to cancel out one variable, solving for the other, then back-substitute to find the second variable. The solution for the system is x = -6 and y = -6, which should be checked for correctness.

Step-by-step explanation:

To solve the system of equations using the elimination method, you can add or subtract the equations to eliminate one variable. Starting with the following two equations:

  1. 7x - 6y = -6
  2. -9x + 6y = 18

These equations are already arranged for elimination, as the coefficients of y are opposites. We can add the two equations together to eliminate the y variable:

7x - 6y + (-9x + 6y) = -6 + 18

This simplifies to:

-2x = 12

Now, divide both sides by -2 to solve for x:

x = -6

Next, we substitute x back into one of the original equations to solve for y. We'll use the first equation:

7(-6) - 6y = -6

-42 - 6y = -6

Add 42 to both sides:

-6y = 36

Finally, divide both sides by -6:

y = -6

We have now determined that x = -6 and y = -6 is the solution to the system of equations.

Remember to always check your solution by substituting the values of x and y back into the original equations to ensure they hold true.

User Jarederaj
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