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Solve by setting the coefficient the same.

Solve by setting the coefficient the same.-example-1
User WinOrWin
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Answer:

(x, y) = (-4, -4)

Explanation:

The coefficients of x will be the same if we multiply the first equation by 3:

-9x +21y = -48

Now, we can solve the system by subtracting the second equation. Since the coefficients of x are the same, the subtraction eliminates x from the equation.

(-9x +21y) - (-9x +5y) = (-48) - (16)

16y = -64 . . . . . . simplify

y = -4 . . . . . . . . . divide by 16

Substituting this value into the first equation, we get ...

-3x +7(-4) = -16

-3x = 12 . . . . . . . add 28

x = -4 . . . . . . . . . divide by -3

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Solve by setting the coefficient the same.-example-1
User Dacre Denny
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