7) -6x + 6y = 6\n-6x + 3y = -12

Explanation:

Step1: Subtract the second equation from the first

Subtract $(-6x + 3y=-12)$ from $(-6x + 6y = 6)$ to eliminate $x$. $(-6x+6y)-(-6x + 3y)=6-(-12)$ $-6x + 6y+6x - 3y=6 + 12$ $3y=18$

Step2: Solve for $y$

Divide both sides of $3y = 18$ by 3. $y=\frac{18}{3}=6$

Step3: Substitute $y = 6$ into the first equation

Substitute $y = 6$ into $-6x+6y = 6$. $-6x+6\times6 = 6$ $-6x+36 = 6$

Step4: Solve for $x$

First, subtract 36 from both sides: $-6x=6 - 36=-30$ Then divide both sides by -6: $x=\frac{-30}{-6}=5$

Answer:

$x = 5,y = 6$