Solve the system by graphing if possible. $$\left\{ \begin{array} { l }
2 x + y = - 7 \
x - 2 y = - 1
\end{array} \right.$$
A) dependent system
B) $x = - 3 y = - 1$
C) $x = - 3 y = 1$
D) $x = 3 y = 1$
E) inconsistent system

Question

Solve the system by graphing if possible. $$\left\{ \begin{array} { l } 
2 x + y = - 7 \
x - 2 y = - 1
\end{array} \right.$$
A) dependent system 
B) $x = - 3 y = - 1$ 
C) $x = - 3 y = 1$ 
D) $x = 3 y = 1$ 
E) inconsistent system

Quizplus · Accepted Answer

To solve the system by graphing, we graph the two lines on the same coordinate plane:
\begin{align*}
2x+y&=-7 \quad \Rightarrow \quad y=-2x-7 \
x-2y&=-1 \quad \Rightarrow \quad y=\frac{1}{2}x+\frac{1}{2}
\end{align*}
The graph intersects at the point $(-3,-1)$, which is the solution to the system. Therefore, the answer is B: $x=-3, y=-1$.

Solve the System by Graphing If Possible {2x+y=−7x−2y=−1\left\{ \begin{array} { l } 2 x + y = - 7 \\x - 2 y = - 1\end{array} \right.{2x+y=−7x−2y=−1​

Solve the System by Graphing If Possible $\left\{ \begin{array} { l } 2 x + y = - 7 \\x - 2 y = - 1\end{array} \right.$