solve using elimination. -3x+y=-12 9x-9y=-18 d square D

To solve the system of equations using elimination, we can follow these steps:

1. Multiply the first equation by 3 to make the coefficients of y in both equations equal:
$$-9x + 3y = -36$$
$$9x - 9y = -18$$

2. Add the two equations together to eliminate y:
$$-9x + 3y + 9x - 9y = -36 - 18$$
$$-6y = -54$$

3. Divide both sides of the equation by -6 to solve for y:
$$y = 9$$

4. Substitute the value of y into one of the original equations to solve for x. Let's use the first equation:
$$-3x + 9 = -12$$
$$-3x = -21$$
$$x = 7$$

Therefore, the solution to the system of equations is $$x = 7$$ and $$y = 9$$ .