algebraic & linear equation

http://www.edugains.ca/newsite/math2/efqmc20103_6.html

http://www.mathworksheetscenter.com/grades/68/

http://www.softschools.com/grades/6th_and_7th.jsp

http://teachers.henrico.k12.va.us/math/hcpsalgebra1/module3-3.html

http://www.math-drills.com/algebra.shtml

http://itech.pensacolastate.edu/falzone/course/1033handouts.htm

http://www.regentsprep.org/Regents/math/ALGEBRA/AE2/indexAE2.htm