Solve the system by the best method. Use set notation to express the solution set.
-$$\left\{ \begin{array} { l }
3 x = - 9 \
x + 5 y = 17
\end{array} \right.$$
A) $\{ ( 3,4 ) \}$
B) no solution; $\varnothing$
C) $\{ ( 3 , - 4 ) \}$
D) $\{ ( - 3,4 ) \}$

Question

Solve the system by the best method. Use set notation to express the solution set.
-$$\left\{ \begin{array} { l } 
3 x = - 9 \
x + 5 y = 17
\end{array} \right.$$
A) $\{ ( 3,4 ) \}$
B) no solution; $\varnothing$
C) $\{ ( 3 , - 4 ) \}$
D) $\{ ( - 3,4 ) \}$

Quizplus · Accepted Answer

Solving the first equation gives $x = -3$. Substituting $x = -3$ into the second equation gives $-3 + 5y = 17$, which simplifies to $5y = 20$, so $y = 4$. Thus, the solution is $(-3, 4)$.

Solve the System by the Best Method {3x=−9x+5y=17\left\{ \begin{array} { l } 3 x = - 9 \\x + 5 y = 17\end{array} \right.{3x=−9x+5y=17​

Solve the System by the Best Method $\left\{ \begin{array} { l } 3 x = - 9 \\x + 5 y = 17\end{array} \right.$