On line 25 you meant cin >> x >> y >> z;
and on line 29 cout << "\n\nThe answer is \n\n" << x << y << z; I suppose...
But that will only show the input of the user.
change x and z to double and output the calculation based on the value of y
1>c:\documents and settings\timbo\my documents\visual studio 2008\projects\calculator\calculator\main.cpp(25) : error C2371: 'x' : redefinition; different basic types
1> c:\documents and settings\timbo\my documents\visual studio 2008\projects\calculator\calculator\main.cpp(14) : see declaration of 'x'
1>c:\documents and settings\timbo\my documents\visual studio 2008\projects\calculator\calculator\main.cpp(25) : error C2371: 'z' : redefinition; different basic types
1> c:\documents and settings\timbo\my documents\visual studio 2008\projects\calculator\calculator\main.cpp(16) : see declaration of 'z'
1>c:\documents and settings\timbo\my documents\visual studio 2008\projects\calculator\calculator\main.cpp(26) : error C2086: 'char y' : redefinition
1> c:\documents and settings\timbo\my documents\visual studio 2008\projects\calculator\calculator\main.cpp(15) : see declaration of 'y'
1>c:\documents and settings\timbo\my documents\visual studio 2008\projects\calculator\calculator\main.cpp(27) : error C2088: '>>' : illegal for class
1>c:\documents and settings\timbo\my documents\visual studio 2008\projects\calculator\calculator\main.cpp(45) : error C2088: '<<' : illegal for class