Question 659444

{{{2x-5y=-46}}}...........1  

{{{x+10y=77}}}............2
______________________________multiply equation 2 by {{{-2}}}

{{{-2x-20y=-154}}}............2........now add 1 and 2

___________________________________


{{{2x-5y=-46}}}...........1 
+
{{{-2x-20y=-154}}}............2
___________________________

{{{2x-2x-5y-20y=-46-154}}}

{{{-5y-20y=-46-154}}}......solve for {{{y}}}

{{{-25y=-200}}}.........both sides multiply by {{{-1}}}

{{{25y=200}}}

{{{y=200/25}}}

{{{highlight(y=8)}}}

now, find {{{x}}}


{{{x+10y=77}}}............2

{{{x+10*8=77}}}

{{{x+80=77}}}

{{{x=77-80}}}

{{{highlight(x=-3)}}}