Question 535506
{{{-5x+2y=-11}}}.............(1)
{{{-5x-2y=1}}}}..............(2)

Add (1) and (2)

{{{-5x+cross(2y)=-11}}}
{{{-5x-cross(2y)=1}}}
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{{{-10x=-10}}}
Divide by -10 both sides
{{{-10x/-10=-10/-10}}}
{{{cross(-10)x/cross(-10)=cross(-10)/cross(-10)}}}
{{{x=1}}}
Put the value of x in (1)
{{{-5x+2y=-11}}}.............(1)
{{{-5(1)+2y=-11}}}
{{{-5+2y=-11}}}
{{{2y=-11+5}}}
{{{2y=-6}}}
Divide by 2 both sides
{{{2y/2=-6/2}}}
{{{cross(2)y/cross(2)=-cross(6)/cross(2)}}}
{{{y=-3}}}
(x,y)=(1,-3)



Check
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Put the values of x and y in (2)
{{{-5x-2y=1}}}..............(2)
{{{-5(1)-2(-3)=1}}}
{{{-5+6=1}}}
{{{1=1}}}