Basic Algebra/Working with Numbers/Chapter Test

Please post your test problems this way:
 * Problem:(answer,level of difficulty(easy, medium, hard))
 * Example 2x=6: (x=3,easy)
 * Example 2x+x^2+x(=3x+x^2(form1 level))
 * Example combine1:2,3:2(=6:4:2)(form2 level)