Question

Solve the following system of equations:

−2x + y = 1
−4x + y = −1

(3, 1)
(−1, 3)
(−1, −3)
(1, 3)

Answer 1

(1,3)

Explanation:

`\sf Answer\begin{cases} \sf \rightarrowtail \: - 2x + y = 1 \dots(1) \\ \sf \rightarrowtail \: - 4x + y = - 1 \dots(2) \\ \sf 2 * (1) \implies - 4x + 2y = 2 \\ \sf 1 * (2) \implies - 4x + y = - 1 \\ \bf \star \: substracting \: both \\ \sf \rightarrowtail \: y = 3 \\ \sf \rightarrowtail \: -2x+(3)=1 \\ \sf \rightarrowtail \: -2x=-2 \\ \sf \rightarrowtail \: x=1\end{cases}`