Solve 5x+4y=-30
3x-9y=-18
Solve using the elimination method

  (x, y) = (-6, 0)

Step-by-step explanation:

The y-coefficients have opposite signs, so we can eliminate y-terms by multiplying both equations by a positive number and adding the results.

9 times the first equation plus 4 times the second gives ...

  9(5x +4y) +4(3x -9y) = 9(-30) +4(-18)

  45x +36y +12x -36y = -270 -72 . . . . eliminate parentheses

  57x = -342 . . . . . collect terms

  x = -6 . . . . . . . divide by the coefficient of x

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Substituting into the first equation gives ...

  5(-6) +4y = -30

  4y = 0 . . . . . . . . . add 30

  y = 0

The solution is (x, y) = (-6, 0).

yes

step-by-step explanation: