Question

find the solution of the system of equations.
9x - 9y = -9
3x + 9y = -15

Explanation:

Step1: Add the two equations

$$(9x - 9y) + (3x + 9y) = -9 + (-15)$$
$$12x = -24$$

Step2: Solve for $x$

$$x = \frac{-24}{12} = -2$$

Step3: Substitute $x=-2$ into second equation

$$3(-2) + 9y = -15$$
$$-6 + 9y = -15$$

Step4: Solve for $y$

$$9y = -15 + 6 = -9$$
$$y = \frac{-9}{9} = -1$$

Answer:

$x=-2$, $y=-1$