Use Compute not Formula in answer

Author: gajennings

OpenProblemLibrary/PCC/BasicAlgebra/Calculator/DesmosSolvingRadicalEquation10.pg

@@ -73,7 +73,7 @@ $ySolution = $c;
 $func0 = Compute("sqrt($a-$b*$var)")->reduce;
 $func1 = Compute("$c")->reduce;
 
-$solution = Formula("$var=$xSolution");
+$solution = Compute("$var=$xSolution");
 
 ##############################################
 TEXT(beginproblem());