Question 19589
x+y=11
x-y=10
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2x=21
{{{x=21/2}}}
{{{x=10&1/2}}}
Substitute {{{x=21/2}}} to x+y=11
x+y=11
{{{21/2+y=11}}}
{{{y=11-21/2}}}
{{{y=22/2-21/2}}}
{{{y=(22-21)/2}}}
{{{y=1/2}}}
Thus, {{{x=10&1/2}}} and {{{y=1/2}}}