Solve the system of equations by the addition method.
-$\left\{ \begin{array} { l }
x + y = 4 \
x - y = 4
\end{array} \right.$
A) $( 0 , - 4 )$
B) $( 4,0 )$
C) $( 0,4 )$
D) $( - 4,0 )$

Question

Solve the system of equations by the addition method.
-$\left\{ \begin{array} { l } 
x + y = 4 \
x - y = 4
\end{array} \right.$
A) $( 0 , - 4 )$
B) $( 4,0 )$
C) $( 0,4 )$
D) $( - 4,0 )$

Quizplus · Accepted Answer

Adding the two equations $x + y + x - y = 4 + 4$ gives $2x = 8$, so $x = 4$. Substituting $x = 4$ into the first equation gives $4 + y = 4$, so $y = 0$. Thus, the solution is $(4, 0)$.

Solve the System of Equations by the Addition Method {x+y=4x−y=4\left\{ \begin{array} { l } x + y = 4 \\x - y = 4\end{array} \right.{x+y=4x−y=4​

Solve the System of Equations by the Addition Method $\left\{ \begin{array} { l } x + y = 4 \\x - y = 4\end{array} \right.$