solve the system by substitution.\n$9x + 3y = -30$\n$-5x = y$

Explanation:

Step1: Substitute y in first - equation

Substitute $y = - 5x$ into $9x + 3y=-30$. We get $9x+3(-5x)=-30$.

Step2: Simplify the equation

$9x - 15x=-30$, which simplifies to $-6x=-30$.

Step3: Solve for x

Divide both sides by - 6. So, $x=\frac{-30}{-6}=5$.

Step4: Solve for y

Substitute $x = 5$ into $y=-5x$. Then $y=-5\times5=-25$.

Answer:

$x = 5,y=-25$