Question 1163926
Using variables t for the tens digit ad u for the units digit, the description is written as {{{system(3t=-2+2u,and,2(10t+u)=20+(t+10u))}}};
and you want to calculate what is {{{10t+u}}}.

.

.

{{{system(-3t+2u=2,19t-8u=20)}}}


{{{system(-12t+8u=8,19t-8u=20)}}}


ADD the equations,....
{{{t=4}}}



{{{2u=3*4+2}}}{{{substitution}}}{{{used}}}:
{{{2u=14}}}
{{{u=7}}}



RESULT:   {{{10t+u=highlight(highlight(47))}}}