Q5. - Algebra 2

Question

5: Solve each system of equation by graphing, substitution, or elimination.

$\begin{array}{c}x+y=-8\\ -3x+2y=9\end{array}$

Step-by-Step Solution

Answer

The solution is $x=-5,y=-3$.

Step-1 – Concept of elimination

The process of adding or subtracting equation to remove a variable and simplify solving the system of equations is called elimination. 

Step-2 – Using elimination to solve the equation

Given equations are-:

$\begin{array}{c}x+y=-8\\ -3x+2y=9\end{array}$

Multiplying first equation by $3$ and adding with second equation, we get

$\begin{array}{c}3y+2y=-24+9\\ 5y=-15\\ y=-3\end{array}$

Step-3– Substituting the value of y in the first equation, we get

$\begin{array}{c}x+y=-8\\ x-3=-8\\ x=-8+3\\ x=-5\end{array}$