Question 1097115
{{{system(n=2r,n=e/2,e+22=2(r+22))}}}

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{{{system(r=n/2,e=2n,e+22=2r+44)}}}


{{{e-2r=22}}}
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Just substitute for r and for e:
{{{2n-n=22}}}
{{{highlight(n=22)}}}