Question 683460
x = tens
y = ones
...
y = 2x
x+y = 12
...
Substitution
x + 2x = 12
3x = 12 ==> divide both sides by 3
{{{highlight_green(x = 4)}}}
...
y = 2(4) = 8
{{{highlight_green(y = 8)}}}
...
The number is  {{{highlight_green(48)}}}
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