solve the system of linear equations by substitution.\n5x + 2y = 9\nx + y = -3

Explanation:

Step1: Isolate a variable in one equation

From $x + y=-3$, we get $x=-3 - y$.

Step2: Substitute into the other equation

Substitute $x=-3 - y$ into $5x+2y = 9$. So $5(-3 - y)+2y=9$. Expand: $-15-5y + 2y=9$. Combine like - terms: $-15-3y=9$. Add 15 to both sides: $-3y=9 + 15$, so $-3y=24$. Divide both sides by - 3: $y=-8$.

Step3: Find the value of the other variable

Substitute $y = - 8$ into $x=-3 - y$. Then $x=-3-(-8)=-3 + 8 = 5$.

Answer:

$x = 5,y=-8$