Solve the system of equations by the substitution method.
-$$\left\{ \begin{array} { r }
x + y = 6 \
y = 2 x
\end{array} \right.$$
A) $( 2 , - 4 )$
B) $( - 2,4 )$
C) $( - 2 , - 4 )$
D) $( 2,4 )$

Question

Solve the system of equations by the substitution method.
-$$\left\{ \begin{array} { r } 
x + y = 6 \
y = 2 x
\end{array} \right.$$
A) $( 2 , - 4 )$
B) $( - 2,4 )$
C) $( - 2 , - 4 )$
D) $( 2,4 )$

Quizplus · Accepted Answer

Substituting $y = 2x$ into the first equation gives $x + 2x = 6$, which simplifies to $3x = 6$. Solving for $x$ gives $x = 2$. Substituting $x = 2$ into $y = 2x$ gives $y = 4$, so the solution is $(2, 4)$.

Solve the System of Equations by the Substitution Method {x+y=6y=2x\left\{ \begin{array} { r } x + y = 6 \\y = 2 x\end{array} \right.{x+y=6y=2x​

Solve the System of Equations by the Substitution Method $\left\{ \begin{array} { r } x + y = 6 \\y = 2 x\end{array} \right.$