Question

-3x+8y=73x-7y=-46 Directions: Solve each system of equations by elimination. Clearly identify your solution.

Answer 1

$\begin{gathered} \text{Let:} \\ -3x+8y=73\text{ (1)} \\ x-7y=-46\text{ (2)} \end{gathered}$

Multiply (2) by 3:

3x - 21y = -138

Add (1) and (2):

$\begin{gathered} \frac{-3x+8y=73}{3x-21y=-138}\text{ +} \\ \\ -13y=-65 \end{gathered}$

Solving for y:

Divide both sides by -13:

$\begin{gathered} \frac{-13y}{-13}=\frac{-65}{-13} \\ y=5 \end{gathered}$

Replace the value of y into (2):

$\begin{gathered} x-7(5)=-46 \\ x-35=-46 \\ \text{solve for x:} \\ x=-46+35 \\ x=-11 \end{gathered}$

Therefore, x = -11 and y = 5