Question 859532
{{{ g = x }}}
{{{ f = g + 6 }}}
{{{ m = 2f }}}
{{{ t = m + x }}}
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By substitution:
{{{ t = 2f + x }}}
{{{ t = 2*( g + 6 ) + x }}}
{{{ t = 2*( x + 6 ) + x }}}
{{{ t = 2x + 12 + x }}}
{{{ t = 3x + 12 }}}
This is Tanya's age in years