To solve this question we will use the elimination method.
Adding 7 times the first equation to 2 times the second equation we get:
[tex]14x+4y+(-14x)+35y=30+(-147)\text{.}[/tex]Simplifying the above equation we get:
[tex]4y+35y=-117.[/tex]Solving for y we get:
[tex]\begin{gathered} 39y=-117, \\ y=-\frac{117}{39}, \\ y=-3. \end{gathered}[/tex]Substituting y=-3 in the first equation, and solving for x we get:
[tex]\begin{gathered} -2x+5(-3)=-21, \\ -2x-15=-21, \\ -2x=-6, \\ x=3. \end{gathered}[/tex]Answer:
[tex]\begin{gathered} x=3, \\ y=-3. \end{gathered}[/tex]