Question 1025645
1.{{{A+B+C=42}}}
.
.
{{{C=(A+B)-2}}}
2.{{{A+B-C=2}}}
.
.
{{{4A=32+(C-B)}}}
3.{{{4A+B-C=32}}}
Add 1 and 2,
{{{A+B+C+A+B-C=42+2}}}
{{{2A+2B=44}}}
3.{{{A+B=22}}}
Add 1 and 3,
{{{A+B+C+4A+B-C=42+32}}}
4.{{{5A+2B=74}}}
Multiply 3 by 2 and subtract from 4,
{{{5A+2B-2A-2B=74-44}}}
{{{3A=30}}}
{{{A=10}}}
Then,
{{{10+B=22}}}
{{{B=12}}}
and finally,
{{{10+12+C=42}}}
{{{C=20}}}