Question

3x+2y=11
7x-y=3
System of equations using multiplication with addition method.

Answer 1

`\it \begin{cases}\ \it 3x+2y=11\\ \\ \it 7x-y=3\bigg|_(\cdot2)\end{cases} \Rightarrow \begin{cases}\ \it 3x+2y=11\\ \\ \it 14x-2y=6\end{cases}\\ \rule{0.2}{0.2}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \rule{120}{0.7}\\ \\ \rule{0.2}{0.2}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ 17x\ \ \ \ \ \bigg|\ \ \ =17\\ \\ \\ 17x=17 \Rightarrow x=1\ \ \ \ \ (*)\\ \\ \\ 7x-y=3\ \stackrel{(*)}{\Longrightarrow} 7-y=3 \Rightarrow y=4\\ \\ \\ S=\{(1,\ \ 4)\}`