Question 1074467
1.{{{A+C=200}}}
2.{{{9A+5C=1420}}}
Multiply eq. 1 by 5 and subtract from eq. 2 to eliminate C.
{{{9A+5C-5A-5C=1420-1000}}}
{{{4A=420}}}
Now solve for A then use either equation to solve for C.