Solve the system by the method of substitution. $\left\{ \begin{aligned}
x - y & = 4 \
7 x - 4 y & = 37
\end{aligned} \right.$
A)(7, 3)
B)(7, -3)
C)(-8, -4)
D)(-7, 3)
E)(8, 4)

Question

Solve the system by the method of substitution.  $\left\{ \begin{aligned}
x - y & = 4 \
7 x - 4 y & = 37
\end{aligned} \right.$ 
A)(7, 3)
B)(7, -3)
C)(-8, -4)
D)(-7, 3)
E)(8, 4)

Quizplus · Accepted Answer

From the first equation, we can express $x$ in terms of $y$ as $x = y + 4$. Substituting this expression for $x$ into the second equation gives $7(y + 4) - 4y = 37$. Simplifying this equation leads to $7y + 28 - 4y = 37$, which further simplifies to $3y = 9$, giving $y = 3$. Substituting $y = 3$ back into the expression $x = y + 4$ gives $x = 3 + 4 = 7$. Therefore, the solution is $x = 7$, $y = 3$, which corresponds to choice A.

Solve the System by the Method of Substitution {x−y=47x−4y=37\left\{ \begin{aligned}x - y & = 4 \\7 x - 4 y & = 37\end{aligned} \right.{x−y7x−4y​=4=37​

Solve the System by the Method of Substitution $\left\{ \begin{aligned}x - y & = 4 \\7 x - 4 y & = 37\end{aligned} \right.$