6 ms·
khan has something similar http://www.khanacademy.org/exercises?exid=linear_equations_1 http://www.khanacademy.org/exercises?exid=linear_equations_1
by patrickaljord 16y ago
khan has something similar http://www.khanacademy.org/exercises?exid=linear_equations_1 http://www.khanacademy.org/exercises?exid=linear_equations_1