Solve the system by graphing if possible. $$\left\{ \begin{array} { l }
x - y = 8 \
2 x + y = 4
\end{array} \right.$$
A) $x = 4 , y = 4$
B) $x = 4 , y = - 4$
C) $x = - 4 , y = - 4$
D) inconsistent system
E) dependent system

Question

Solve the system by graphing if possible. $$\left\{ \begin{array} { l } 
x - y = 8 \
2 x + y = 4
\end{array} \right.$$
A) $x = 4 , y = 4$ 
B) $x = 4 , y = - 4$ 
C) $x = - 4 , y = - 4$ 
D) inconsistent system 
E) dependent system

Quizplus · Accepted Answer

To solve by graphing, we can rewrite the equations in slope-intercept form:
$$\begin{aligned} x - y &= 8 \quad \implies \quad y = x-8 \ 2x+y &= 4 \quad \implies \quad y = -2x+4 \end{aligned}$$
Then, we can plot the two lines:

![Graph](https://i.imgur.com/NIov9Px.png)

We can see that the lines intersect at the point $(4,-4)$. Therefore, the solution to the system is $x=4$ and $y=-4$, which corresponds to choice B.

Solve the System by Graphing If Possible {x−y=82x+y=4\left\{ \begin{array} { l } x - y = 8 \\2 x + y = 4\end{array} \right.{x−y=82x+y=4​

Solve the System by Graphing If Possible $\left\{ \begin{array} { l } x - y = 8 \\2 x + y = 4\end{array} \right.$