1Use different ways to find S.S.
2Analyse the S.S.
3know the meaning of solution set.
4Find the S.S.
5Recognize 'what does S.S. means'.
6Solve the equation.
7Understand the special cases.
8Apply the lesson in our real life.
9chick the solution using many ways.
10Solving two equations from the first degree in two variables.