Answer:
Step-by-step explanation:
[tex]\left\{\begin{array}{ccc}-x+y=5\\4x+y=10&\text{change the signs}\end{array}\right\\\underline{+\left\{\begin{array}{ccc}-x+y=5\\-4x-y=-10\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad-5x=-5\qquad\text{divide both sides by (-5)}\\.\qquad x=1\\\\\text{put the value of x to the first equation}\\-1+y=5\qquad\text{add 1 to both sides}\\y=6[/tex]