Solve the system of equations 3x-6y=-393x-6y=-39 and - 3x+4y=9-3x+4y=9 by combining the equations.

(x, y) = (17, 15)

Step-by-step explanation:

Adding the two equations gives ...

(3x - 6y) + (-3x + 4y) = (-39) + (9)

-2y = - 30

y = 15

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Substituting this value of y into the second equation, we get ...

-3x + 4 (15) = 9

-3x = - 51

x = 17

The solution is (x, y) = (17, 15).