<PRE><B>Question 960020</B>
.
A=adult tickets; C=child tickets
A+C=56
A=56-C
$4.50A+$3.50C=$215 Substitute for A
$4.50(56-C)+$3.50C=$215
$252-$4.50C+$3.50C=$215  Subtract $252 from each side.
-$1.00C=-$37 Divide each side by(-$1)
C=37 ANSWER 1: She sold 37 child tickets.
A=56-C=56-37=19 ANSWER 2: She sold 19 Adult tickets.
CHECK:
$4.50A+$3.50C=$215.00 
$4.50(19)+$3.50(37)=$215.00 
$85.50+$129.50=$215.00
$215=$215
</PRE>